Showing posts with label Reality. Show all posts
Showing posts with label Reality. Show all posts

05 October 2018

Quantum Bullshit

I was appalled recently to see that a senior professor of Buddhism Studies—whose work on Chinese Buddhist texts I much admire—had fallen into the trap of trying to compare some concept from Buddhist philosophy to what he calls "quantum mechanics". Unfortunately, as seems almost inevitable in these cases, the account the Professor gives of quantum mechanics is a hippy version of the Copenhagen interpretation proposed by Werner Heisenberg back in the 1920s. In a further irony, this same Professor has been a vocal critic of the secularisation and commercialisation of Buddhist mindfulness practices. The same problems that he identifies in that case would seem to apply to his own misappropriation of quantum mechanics.

As I've said many times, whenever someone connected with Buddhism uses the word "quantum" we can safely substitute the word "bullshit". My use of the term "bullshit" is technical and based on the work of Princeton philosopher Harry Frankfurt (image left). I use "bullshit" to refer to a particular rhetorical phenomenon. Here is the anonymous summary from Wikipedia, which I think sums up Frankfurt's arguments about bullshit precisely and concisely:
“Bullshit is rhetoric without regard for truth. The liar cares about the truth and attempts to hide it; the bullshitter doesn't care if what they say is true or false; only whether or not their listener is persuaded.”
What I am suggesting is that Buddhists who refer to quantum mechanics are not, in fact, concerned with truth, at all. A liar knows the truth and deliberately misleads. The bullshitter may or may not know or tell the truth, but they don't care either way. Their assertions about quantum mechanics may even be true, but this is incidental. The idea is to persuade you of a proposition which may take several forms but roughly speaking it amounts to:
If you sit still and withdraw attention from your sensorium, another more real world is revealed to you.
Certain Buddhists argue that a specific man sitting under a specific tree ca 450 BCE, while ignoring his sensorium, saw such a reality (Though he neglected to mention this). And then this thesis is extended with the proposition:
The reality that one "sees" when one's eyes are closed is very like the descriptions (though not the mathematics) of quantum mechanics.
I imagine that these statements strike most scientists as obviously false. The first hint we had of a quantum world was in 1905 when Einstein formalised the observation that energy associated with atoms comes in discrete packets, which he called "quanta" (from the Latin with the sense "a portion"; though, literally, "how much?"). Even this nanoscale world, which we struggle to imagine, is established by observation, not by non-observation. Equally, there is no sign in early Buddhist texts that the authors had any interest in reality, let alone ultimate reality. They didn't even have a word that corresponds to "reality". They did talk a lot about the psychology of perception and about the cessation of perception in meditation, within the context of a lot of Iron Age mythology. Given that there is no prima facie resemblance between science and Buddhism whatever, we might well ask why the subject keeps coming up.

I think this desire to positively compare Buddhism to quantum mechanics is a form of "virtue signalling". By attempting to align Buddhist with science, the highest form of knowledge in the modern world, we hope to take a ride on the coat-tails of scientists. This is still the Victorian project of presenting the religion of Buddhism as a "rational" alternative to Christianity. Generally speaking, Buddhists are as irrational as any other religieux, it's just that one of the irrational things Buddhists believe is that they are super-rational.

Had it merely been another misguided Buddhism Studies professor, I might have let it go with some pointed comments on social media. Around the same time, I happened to watch a 2016 lecture by Sean Carroll on YouTube called, Extracting the Universe from the Wave Function. Then I watched a more recent version of the same lecture from 2018 delivered at the Ehrenfest Colloquium. The emphasis is different in the two forums and I found that watching both was useful. Both lectures address the philosophy of quantum mechanics, but in a more rigorous way than is popular amongst Buddhists. Sean thinks the Copenhagen interpretation is "terrible" and he convinced me that he is right about this. The value of the lectures is that one can get the outlines of an alternative philosophy of quantum mechanics and with it some decisive critiques of the Copenhagen interpretation. Sean is one of the leading science communicators of our time and does a very good job of explaining this complex subject at the philosophical level.

What is Quantum Mechanics?

It is perhaps easiest to contrast quantum mechanics with classical mechanics. Classical mechanics involves a state in phase space (described by the position and momentum of all the elements) and then some equations of motion, such as Newton's laws, which describe how the system evolves over time (in which the concept of causation plays no part). Phase space has 6n dimensions, where n is the number of elements in the state. Laplace pointed out that given perfect knowledge of such a state at a given time, one could apply the equations of motion to know the state of the system at any time (past or future).

Quantum mechanics also minimally involves two things. A state is described by a Hilbert Space, the set of all possible quantum states, i.e., the set of all wave functions, Ψ(x). It is not yet agreed whether the Hilbert Space for our universe has an infinite or merely a very large number of dimensions.

For the STEM people, there's a useful brief summary of Hilbert spaces here. If you want an image of what a Hilbert Space is like, then it might be compared to the library in the short story The Library of Babel, by Jorge Luis Borges. (Hat-tip to my friend Amṛtasukha for this comparison).

Mathematically, a Hilbert Space is a generalisation of vector spaces which satisfy certain conditions, so that they can be used to describe a geometry (more on this later). One thing to watch out for is that mathematicians describe Hilbert Spaces (plural). Physicists only ever deal with the quantum Hilbert Space of all possible wavefunctions and have slipped into the habit talking about "Hilbert Space" in the singular. Sean Carroll frequently reifies "Hilbert Space" in this way. Once we agree that we are talking about the space defined by all possible wave functions, then it is a useful shorthand. We don't have to consider any other Hilbert Spaces.

The second requirement is an equation that tells us how the wave functions in Hilbert Space evolve over time. And this is Schrödinger's wave equation. There are different ways of writing this equation. Here is one of the common ways:

The equation is a distillation of some much more complex formulas and concepts that take a few years of study to understand. Here, i is the imaginary unit (defined as i2 = -1), ħ is the reduced Planck constant (h/2π). The expression δ/δt represents change over time. Ψ represents the state of the system as a vector in Hilbert Space -- specifying a vector in a space with infinite dimensions presents some interesting problems. Ĥ is the all important Hamiltonian operator which represents the total energy of the system. And note that this is a non-relativistic formulation.

We owe this formalisation of quantum theory to the fact that John von Neumann studied mathematics with David Hilbert in the early 20th Century. Hilbert was, at the time, trying to provide physics with a more rigorous approach to mathematics. In 1915, he invited Einstein to lecture on Relativity at Göttingen University and the two of them, in parallel, recast gravity in terms of field equations (Hilbert credited Einstein so no dispute arose between them). In 1926, Von Neumann showed that the two most promising approaches to quantum mechanics—Werner Heisenberg's matrix mechanics and Erwin Schrödinger's wave equation—could be better understood in relation to a Hilbert Space.

[I'm not sure, but this may the first time a Buddhist has ever given even an overview of the maths in an essay about Buddhism and quantum mechanics.]

By applying the Born Rule (i.e., finding the square of the Wave Function) we can find the probability that any given particle will be found in some location at any given time. A common solution to the wave equation is a map of probabilities. For example, the probability plot for an electron in a resting state hydrogen atom looks like this (where shading represents the range probability and the black in the middle is the nucleus). And btw this is a 2D representation of what in 3D is a hollow sphere.

If we give the electron more energy, the probably map changes in predictable ways. An electron bound to an atom behaves a bit like a harmonic oscillator. A good example of a harmonic oscillator is a guitar string. If you pluck a guitar string you get a complex waveform made from the fundamental mode plus harmonics. The fundamental mode gives a note its perceived pitch, while the particular mixture of harmonics is experienced as the timbre of the note. The fundamental mode has two fixed points at the ends where there is zero vibration, and a maximum in the centre. The next mode, the 2nd harmonic takes more energy to produce and the string vibrates with three minima and two maxima - the pitch is an octave above the fundamental.

Using the fleshy parts of the fingers placed at minima points, it is possible to dampen extraneous vibrations on a guitar string and pick out the harmonics. Such notes have a very different timbre to regular notes. An electron bound to an atom also has "harmonics", though the vibrational modes are three dimensional. One of the striking experimental confirmations of this comes if we split sunlight up into a rainbow, we observe dark patches corresponding to electrons absorbing photons of a precise energy and becoming "excited". One of the first confirmations of quantum mechanics was that Schrödinger was able to accurately predict the absorption lines for a hydrogen atom using it.

And on the other hand, after we excite electrons in, say, a sodium atom, they return to their resting state by emitting photons of a precise frequency (in the yellow part of the visible spectrum) giving sodium lamps their characteristic monochromatic quality. The colour of light absorbed or emitted by atoms allows us to use light to detect them in spectral analysis or spectroscopy. For example, infrared light is good for highlighting molecular bonds; while green-blue visible and ultraviolet light are good for identifying individual elements (and note there are more dark patches towards the blue end of the spectrum).

The wave function applied to the electron in an atom gives us a map of probabilities for finding the electron at some point. We don't know where the electron is at any time unless it undergoes some kind of physical interaction that conveys location information (some interactions won't convey any location information). This is one way of defining the so-called the Measurement Problem.
rugby ball

I have a new analogy for this. Imagine a black rugby ball on a black field, in the dark. You are walking around on the field, and you know where you are from a GPS app on your phone, but you cannot see anything. The only way to find the ball is to run around blindly until you kick it. At the moment you kick the ball the GPS app tells you precisely where the ball was at that moment. But kicking the ball also sends it careering off and you don't know where it ends up.

Now, Buddhists get hung up on the idea that somehow the observer has to be conscious, that somehow consciousness (whatever that word means!) is involved in determining how the world evolves in some real sense. As Sean Carroll, says in his recent book The Big Picture:
“...almost no modern physicists think that 'consciousness' has anything whatsoever to do with quantum mechanics. There are an iconoclastic few who do, but it's a tiny minority, unrepresentative of the mainstream” (p.166).
The likes of Fritjof Capra have misled some into thinking that the very vague notion of consciousness plays a role in the measurement problem. As far as the mainstream of quantum mechanics is concerned, consciousness plays no part whatsoever in quantum mechanics. And even those who think it does have provided no formalism for this. There is no mathematical expression for "consciousness", "observer", or "observation". All of these concepts are completely nebulous and out of place around the wave equation, which predicts the behaviour of electrons at a level of accuracy that exceeds the accuracy of our measurements. In practice, our experiments produce data that matches prediction to 10 decimal places or more. Quantum mechanics is the most accurate and precise theory ever produced. "Consciousness" is the least well-defined concept in the history of concepts. "Observation" is not even defined.

In the image of the black rugby ball on a black field in the dark, we don't know where the ball is until we kick it. However, a ball and a field are classical. In the maths of quantum mechanics, we have no information about the location of the ball until we physically interact with it. Indeed, it appears from the maths that it's not physically in one place until information about location is extracted from the system through a physical interaction. And by this we mean, not a conscious observer, but something like bouncing some radiation off the electron. It's as though every time you take a step there is a possibility of the ball being there and you kicking it, and at some point, it is there and you kick it. But until that moment, the ball is (somehow) smeared across the whole field all at once.

Put another way, every time we take a step there is some probability that the ball is there and we kick it, and there is some probability that the ball is not there and we do not kick it. But as we step around, we don't experience a probability, and we never experience a ball spread out over all locations. Whenever we interact with the system we experience the ball as being at our location or at some specific other location. Accounting for this is at the heart of different interpretations of quantum mechanics.


What every undergraduate physics student learns is the Copenhagen Interpretation of the measurement problem. In this view, the ball is literally (i.e., in reality) everywhere at once and only adopts a location at the time of "measurement" (although measurement is never defined). This is called superposition - literally "one thing on top of another". Superposition is a natural outcome of the Wave Equation; there are huge problems with the Copenhagen interpretation of how mathematical superposition relates to reality.

Firstly, as Schrödinger pointed out with his famous gedanken (thought) experiment involving a cat, this leads to some very counterintuitive conclusions. In my analogy, just before we take a step, the rugby ball is both present and absent. In this view, somehow by stepping into the space, we make the ball "choose" to be present or absent.

Worse, the Copenhagen Interpretation assumes that the observer is somehow outside the system, then interacts with it, extracting information, and then at the end is once again separate from the system. In other words, the observer behaves like a classic object while the system being observed is quantum, then classical, then quantum. Hugh Everett pointed out that this assumption of Copenhagen is simply false.

In fact, when we pick up the cat to put it in the box, we cannot avoid becoming entangled with it. What does this mean? Using the ball analogy if we kick the ball and know its location at one point in time then we become linked to the ball, even though in my analogy we don't know where it is now. If someone else now kicks it, then we instantaneously know where the ball was when it was kicked a second time, wherever we happen to be on the field. It's as though we get a GPS reading from the other person sent directly to our phone. If there are two entangled electrons on either side of the universe and we measure one of them and find that it has spin "up", then we also know with 100% certainty that at that same moment in time, the other electron has spin "down". This effect has been experimentally demonstrated so we are forced to accept it until a better explanation comes along. Thus, in Schrödinger's gedanken experiment, we always know from instant to instant what state the cat is in (this is also counter-intuitive, but strictly in keeping with the metaphor as Schrödinger outlined it).

As you move about the world during your day, you become quantum entangled with every object you physically interact with. Or electrons in atoms that make up your body become entangled with electrons in the objects you see, taste, touch, etc. Although Copenhagen assumes a cut off (sometimes called Heisenberg's cut) between the quantum world and the classical world, Hugh Everett pointed out that this assumption is nonsense. There may well be a scale on which classical descriptions are more efficient ways of describing the world, but if one atom is quantum, and two atoms are, and three, then there is, in fact, no number of atoms that are not quantum, even if their bulk behaviour is different than their individual behaviour. In other words, the emergent behaviour of macro objects notwithstanding, all the individual atoms in our bodies are obeying quantum mechanics at all times. There is no, and can be no, ontological cut off between quantum and classical, even if there is an epistemological cutoff.

In terms of Copenhagen, the argument is that wave function describes a probability of the ball being somewhere on the field and that before it is kicked it is literally everywhere at once. At the time of kicking the ball (i.e., measurement) the wave function "collapses" and the ball manifests at a single definite location and you kick it. But the collapse of the wave function is a mathematical fudge. In fact, it says that before you look at an electron it is quantum, but when you look at it, it becomes classical. Then when you stop looking it becomes quantum again. This is nonsense.

In Schrödinger's cat-in-the-box analogy, as we put the cat in the box, we become entangled with the cat; the cat interacts with the box becoming entangled with it; and so on. How does an observer ever stand outside a system in ignorance and then interact with it to gain knowledge? The answer is that, where quantum mechanics applies, we cannot. The system is cat, box, and observer. There is no such thing as an observer outside the system. But it is even worse because we cannot stop at the observer. The observer interacts with their environment over a period of years before placing the cat in the box. And both cat and box have histories as well. So the system is the cat, the box, the observer, and the entire universe. And there is no way to get outside this system. It's not a matter of whether we (as macro objects) are quantum entangled, but to what degree we are quantum entangled.

This is a non-trivial objection because entanglement is ubiquitous. We can, in theory, speak of a single electron orbiting a single nucleus, but in reality all particles are interacting with all other particles. One can give a good approximation, and some interactions will be very weak and therefore can be neglected for most purposes but, in general, the parts of quantum systems are quantum entangled. Carroll argues that there are no such things as classical objects. There are scale thresholds above which classical descriptions start to be more efficient computationally than quantum descriptions, but the world itself is never classical; it is always quantum. There is no other option. We are made of atoms and atoms are not classical objects.

Carroll and his group have been working on trying to extract spacetime from the wave function. And this is based on an idea related to entanglement. Since 99.99% of spacetime is "empty" they ignore matter and energy for the moment. The apparently empty spacetime is, in fact, just the quantum fields in a resting state. There is never nothing. But let's call it empty spacetime. One can define a region of spacetime in terms of a subset of Hilbert Space. And if you take any region of empty spacetime, then it can be shown to experience some degree of entanglement with all the other regions nearby. In fact, the degree of entanglement is proportional to the distance. What Carroll has suggested is that we turn this on its head and define distance as a function of quantum entanglement between regions of spacetime. Spacetime would then be an emergent property of the wave function. They have not got a mathematical solution to the wave equation which achieves this, but it is an elegant philosophical overview and shows early promise. Indeed, in a much simplified theoretical universe (with its own specific Hilbert Space, but in which Schrödinger's wave equation applies), they managed to show that the degree of entanglement of a region of spacetime determined its geometry in a way that was consistent with general relativity. In other words, if the maths works out they have shown how to extract quantum gravity from just Hilbert Space and the wavefunction.

Other questions arise from this critique of Copenhagen. What is an "event"? What is an "observation"? The problem for Buddhists is that we assume that it has something to do with "consciousness" and that "consciousness" has something to do with Buddhism. The first is certainly not true, while the second is almost certainly not true depending on how we define consciousness. And defining consciousness is something that is even less consensual than interpreting the measurement problem. There are as many definitions as there are philosophers of mind. How can something so ill-defined be central to a science that is all about well-defined concepts?

More on Interpretations

In 2013, some researchers quizzed physicists at a conference about their preferred interpretation of the measurement problem. This gave rise to what Sean Carroll called The Most Embarrassing Graph in Modern Physics:

Sean Carroll comments:
I’ll go out on a limb to suggest that the results of this poll should be very embarrassing to physicists. Not, I hasten to add, because Copenhagen came in first, although that’s also a perspective I might want to defend (I think Copenhagen is completely ill-defined, and shouldn’t be the favorite anything of any thoughtful person). The embarrassing thing is that we don’t have agreement.

Just 42% of those surveyed preferred Copenhagen - the account of quantum mechanics they all learned as undergraduates. Mind you, Carroll's preferred interpretation, Everett, got even less at 18%. However, it may be more embarrassing than it looks, because there are multiple Everettian interpretations. And note that several existing interpretations had no supporters amongst those surveyed (the survey was not representative of the field).

In Carroll's account, Copenhagen has fatal flaws because it makes unsupportable assumptions. So what about the alternatives? I found Carroll's explanation of the Everett interpretation in this lecture quite interesting and compelling. It has the virtue of being parsimonious.

Just like other interpretations, Everett began with Hilbert Space and the Wave Equation. But he stopped there. There are no special rules for observers as classical objects because there are no classical objects (just classical descriptions). In this view, the rugby ball still both exists and does not exist, but instead of the wave function collapsing, the interaction between the ball, the field, the observer, and the world cause "decoherence". If there are two possible outcomes — ball present at this location, ball somewhere else — then both happen, but decoherence means that we only ever see one of them . The other possibility also occurs, but it is as though the world has branched into two worlds: one in which the ball is present and we kick it, and one in which it is somewhere else and we do not kick it. And it turns out that having split in this way there is no way for the two worlds to interact ever again. The two outcomes are orthogonal in Hilbert Space.

While this sounds counterintuitive, Carroll argues that the many worlds are already present in the Hilbert Space and all the other interpretations have to introduce extra rules to make those other worlds disappear. And in the case of Copenhagen, the extra rules are incoherent. Everett sounds plausible enough in itself, but given the number of particles in the universe and how many interactions there are over time, the number of worlds must be vast beyond imagining. And that is deeply counter-intuitive. However, being counter-intuitive is not an argument against a theory of quantum mechanics. Physics at this scale is always going to be counterintuitive because it's not like the world on the scale we can sense. And at this point, it will be useful to review some of the problems associated with differences in scale.

Scale (again)

I've written about scale before. It is such an important idea and so many of our misconceptions about the world at scales beyond those our senses register are because we cannot imagine very small or very large scales.

We understand our world as classical. That's what we evolved for. Modern humans have been around for roughly between 400,000 and 200,000 years. But we discovered that there are scales much smaller than we can experience with our senses only about 400 years ago with the development of the microscope. As our understanding progressed we began to see evidence of the world on smaller and smaller scales. Each time we had to adjust our notions of the universe. At the same time telescopes revealed a very much larger universe than we had ever imagined.

Quantum mechanics developed from Einstein's articles in 1905 and was formalised mathematically in the 1920s. It has never been intuitive and it is so very far from our experience that is unlikely ever to be intuitive.

Humans with good eyesight can see objects at around 0.1 mm or 100 µm. A human hair is about 20-200 µm. A small human cell like a sperm might be 10 µm, and not visible; while a large fat cell might be 100 µm and be visible (just). A water molecule is about 0.0003 µm or 0.3 nanometres (nm = 10-9 m). But at this level, the physical dimensions of an object become problematic because the location in space is governed by quantum mechanics and is a probability. Indeed, the idea of the water molecule as an "object" is problematic. The classical description of the world breaks down at this scale. The average radius of a hydrogen atom at rest is calculated to be about 25 picometres or 25x10-12 m, but we've already seen that the location of the electron circling the hydrogen nucleus is a probability distribution. We define the radius in terms of an arbitrary cut off in probability. The estimated radius of an electron is less than 10−18 m (though estimates vary wildly). And we have to specify a resting state atom, because in a state of excitation the electron probability map is a different shape. It hardly makes sense to think of the electron as having a fixed radius or even as being an object at all. An electron might best be thought of as a perturbation in the electromagnetic field.

The thing is that, as we scale down, we still think of things in terms of classical descriptions and we don't understand when classical stops applying. We cannot help but think in terms of objects, when, in fact, below the micron scale this gradually makes less and less sense. Given that everything we experience is on the macro scale, nothing beyond this scale will ever be intuitive.

As Sean Carroll says, the many worlds are inherent in Hilbert Space. Other theories have to work out how to eliminate all of the others in order to leave the one that we observe. Copenhagen argues for something called "collapse of the wave function". Why would a wave function collapse when you looked at it? Why would looking at something cause it to behave differently? What happened in the universe before there were observers? Everett argued that this is an artefact of thinking of the world in classical terms. He argued that, in effect, there is no classical world, there is only a quantum world. Subatomic particles are just manifestations of Hilbert Space and the Wave Equation. The world might appear to be classical on some scales, but this is just an appearance. The world is fundamentally quantum, all the time, and on all scales.

Thinking in these terms leads to new approaches to old problems. For example, most physicists are convinced that gravity must be quantised like other forces. Traditional approaches have followed the methods of Einstein. Einstein took the Newtonian formulation of physical laws and transformed them into relativity. Many physicists take a classical expression of gravity and attempt to reformulate it in quantum terms - leading to string theory and other problematic approaches. Carroll argues that this is unlikely to work because it is unlikely that nature begins with a classical world and then quantises it. Nature has to be quantum from the outset and thus Everett was on right track. And, if this is true, then the only approach that will succeed in describing quantum gravity will need to start with quantum theory and show how gravity emerges from it. As I say, Carroll and his team have an elegant philosophical framework for this and some promising preliminary results. The mathematics is still difficult, but they don't have the horrendous and possibly insurmountable problems of, say, string theory.

Note: for an interesting visualisation the range of scales, see The Scale of the Universe.


Quantum mechanics is a theory of how subatomic particles behave. It minimally involves a Hilbert Space of all possible wave functions and the Schrödinger wave equation describing how these evolve over time. Buddhism is a complex socio-religious phenomenon in which people behave in a wide variety of ways that have yet to be described with any accuracy. It's possible that there is a Hilbert Space of all possible social functions and an equation which describes how it evolves over time, but we don't have it yet!

Buddhists try to adopt quantum mechanics, or to talk about quantum mechanics, as a form of virtue signalling -- "we really are rational despite appearances", or legitimising. They either claim actual consistency between Buddhism and quantum mechanics; or they claim some kind of metaphorical similarity, usually based on the fallacy that the measurement problem requires a conscious observer. And this is patently false in both cases. It's not even that Buddhists have a superficial grasp of quantum mechanics, but that they have a wrong grasp of it or, in fact, that they have grasped something masquerading as quantum mechanics that is not quantum mechanics. None of the Buddhists I've seen talking or writing about quantum mechanics mention Hilbert Spaces, for example. I'm guessing that none of them could even begin to explain what a vector is let alone a Hilbert Space.

I've yet to see a Buddhist write about anything other than the Copenhagen interpretation. I presume because it is only the Copenhagen interpretation that is capable of being shoehorned into a narrative that suits our rhetorical purposes; I don't see any advantage to Buddhists in the Everett interpretation, for example. Buddhists read — in whacky books for whacky people — that the "observer" must be a conscious mind. Since this suits their rhetorical purposes they do not follow up and thus never discover that the idea is discredited. No one ever stops to wonder what the statement means, because if they did they'd see that it's meaningless.

Thus, Buddhists who use quantum mechanics to make Buddhism look more interesting are not concerned with the truth. They do not read widely on the subject, but simply adopt the minority view that chimes with their preconceptions and use this as a lever. For example, I cannot ever recall such rhetoric ever making clear that the cat-in-the-box thought experiment was proposed by Schrödinger to discredit the Copenhagen interpretation. It is presented as the opposite. Again, there is a lack of regard for the truth. Nor do Buddhists ever present criticisms of the Copenhagen interpretations such as those that emerge from Everett's interpretation. Other criticisms are available.

And this disregard for the truth combined with a concerted attempt to persuade an audience of some arbitrary argument is classic bullshit (as described by Harry Frankfurt). Buddhists who write about quantum mechanics are, on the whole, bullshitters. They are not concerned with the nature of reality, they are concerned with status, especially the kind of status derived from being a keeper of secret knowledge. It's past time to call out the bullshitters. They only hurt Buddhism by continuing to peddle bullshit. The irony is that the truth of Buddhism is far more interesting than the bullshit; it's just much harder to leverage for status or wealth.


Frankfurt, Harry G. On Bullshit. Princeton University Press.

For those concerned about the flood of bullshit there is an online University of Washington course Calling Bullshit.

If you have a urge to learn some real physics (as opposed to the bullshit Buddhist physics) then see Leonard Susskind's lecture series The Theoretical Minimum. This aims to teach you only what you need to know to understand and even do physics (no extraneous mathematics or concepts).

17 February 2017

Experience and Reality

"Our relation to the world is not that of a thinker to an object of thought"
—Maurice Merleau Ponty. The Primacy of Perception and Its Philosophical Consequences.


In this essay and some to follow, I want to look an an error that many philosophers and most meditators seem to make: the confusion of epistemology and ontology; i.e., the mixing up of experience and reality. This essay will outline and give examples of a specific version of this confusion in the form of the mind projection fallacy.

I agree with those intellectuals who think that we do not ever experience reality directly. This is where I part ways with John Searle who, for reasons I cannot fathom, advocates naïve realism, the view that reality is exactly as we experience it. On the other hand, I also disagree with Bryan Magee that reality is utterly different from what we experience and we can never get accurate and precise knowledge about it. He takes this view to be a consequence of transcendental idealism, but I think it's a form of naïve idealism.

The knowledge we get via inference is not complete, but we can, and do, infer accurate and precise information about objects. This makes a mind-independent reality seem entirely plausible and far more probable than any of the alternatives. So, we are in a situation somewhere between naïve realism and naïve idealism. 

This distinction between a mind-independent reality and the mind is not ontological, but epistemological. The set of reality includes all minds. However, the universe would exist, even if there were no beings to witness is. The universe is not dependent on having conscious observers. So by "reality" I just mean the universe generally; i.e., the universe made up from real matter-energy fields arranged into real structures that have emergent properties, one of which is conscious states. And by "mind" I specifically mean the series of conscious states that inform human beings about the universe. 

What I don't mean is reality in the abstract. I'm deeply suspicious of abstractions at present. For the same reason, I avoid talking about conscious states in the abstract as "consciousness". Things can be real without there necessarily being an abstract reality. Reality is the set of all those things to which the adjective "real" applies. Things are real if they exist and have causal potential. Members of this set may have no other attributes in common. Unfortunately, an abstract conception of reality encourages us to speculate about the "nature of reality", as though reality were something more than  a collection of real things, more than an abstraction. Being real is not magical or mystical.

I'm not making an ontological distinction between mental and physical phenomena. I think an epistemological distinction can be made because, clearly, our experience of our own minds has a different perspective to our experience of objects external to our body, but in the universe there are just phenomena. This is a distinct position from materialism, which privileges the material over the mental. What I'm saying is that what we perceive as "material" and "mental" are not different at the level of being.  

When we play the game of metaphysics and make statements about reality, they arise from inferences about experience. There are three main approaches to this process:
  • we begin with givens and use deduction to infer valid conclusions.
  • we begin with known examples and use induction to infer valid generalisations.
  • we begin with observations and use abductions to infer valid explanations.
We can and do make valid inferences about the universe from experience. The problem has always been that we make many invalid inferences as well. And we cannot always reliably tell valid from invalid.

For example, we know that if you submerge a person in water they will drown. That tells us something about reality. However, for a quite a long time, Europeans believed that certain women were in league with the devil. They believed that witches could not be drowned. So they drowned a lot of women to prove they were not witches; and burned the ones who didn't drown. The central problem here being that witches, as understood by the witch-hunters, did not exist. The actions of some women were interpreted through an hysterical combination of fear of evil and fear of women, and from this witches were inferred to be real. It was a repulsive and horrifying period of our history in which reasoning went awry. But it was reasoning. And it was hardly an isolated incident. Reasoning very often goes wrong. Still. And that ought to make us very much more cautious about reasoning than most of us are.

One of the attractions of the European Enlightenment is that it promised that reason would free us from the oppression of superstition. This has happened to some extent, but superstition is still widespread. Confusions about how reason actually works are only now being unravelled. And this meant that the early claims of the Enlightenment were vastly overblown. If our views about the universe are formed by reasoning, then we have to assume that we're wrong most of the time, unless we have thoroughly reviewed both our view and our methods, and compared notes with others in an atmosphere of critical thinking, which combines competition and cooperation. The latter is science at its best, though admittedly scientists are not always at their best. 

Into this mix comes Buddhism with its largely medieval worldview, modified by strands of modernism. Buddhists often claim to understand the "true nature of reality"; aka The Absolute, The Transcendental, The Dhamma-niyāma, śūnyatā, tathatā,  pāramārthasatya, prajñāpāramitā, nirvāṇa, vimokṣa, and so on. Reality always seems to boil down to a one word answer. And this insight into "reality" is realised by sitting still with one's eyes closed and withdrawing attention from the sensorium in order to experience nothing. Or by imagining that one is a supernatural being in the form of an Indian princess, or a tame demon, or an idealised Buddhist monk, etc. Or any number of other approaches that have in common that seem to take the approach of trying to develop a kind of meta-awareness of our experience.To experience ourselves experiencing.

It's very common to interpret experience incorrectly. As we know the lists of identified cognitive biases and logical fallacies, which each have over one hundred items. From these many problems I want to highlight one. When we make inferences about reality we are biased towards seeing our conclusions, generalisations, and explanations as valid, and to believing that our interpretation is the only valid interpretation. This is the mind projection fallacy.

The Sunset Illusion

An excellent illustrative example of the mind projection fallacy is the sunset. If I stand on a hill and watch the sunset, it seems to me that the the hill and I are fixed in place and the sun is moving relative to me and the hill. Hence, we say "the sun is setting". In fact, we're known for centuries that the sun is not moving relative to the earth, but instead the hill and I are pivoting away on an axis that goes through the centre of the earth. So why do we persist in talking about sunsets?

The problem is that I have internal sensors that tell me when I'm experiencing acceleration: proprioception (sensing muscle/tendon tension) kinaesthesia (sensing joint motion and acceleration) and the inner-ear's vestibular system (orientation to gravity and acceleration). I can also use my visual sense to detect whether I am in motion relative to nearby objects. A secondary way of detecting acceleration is the sloshing around of our viscera creating pressure against the inside of our body.

My brain integrates all this information to give me accurate and precise knowledge about whether my body is in motion. And standing on a hill, watching a sunset, my body is informing me, quite unequivocally, that I am at rest.

I'm actually spinning around the earth's axis of rotation at ca. 1600 km/h or about 460 m/s. That's about Mach 1.5! And because velocity is a vector (it has both magnitude and direction) moving in a circle at a uniform speed is acceleration, because one is constantly changing direction. So why does it not register on our senses? After all, being on a roundabout rapidly makes me dizzy and ill; a high speed turn in a vehicle throws me against the door. It turns out that the acceleration due to going moderately fast in very large circle, is tiny. So small that it doesn't register on any of our onboard motion sensors. The spinning motion does register in the atmosphere and oceans where it creates the Coriolis effect.

Everyone watching a sunset experiences themselves at rest and the sun moving. It is true, but counterintuitive, to suggest that the sun is not moving. Let's call this the sunset illusion.

I'm not sure where it comes from, but in the Triratna Order we often cite four authorities for believing some testimony: it makes sense (reason), it feels right (emotion), it accords with experience (memory), and it accords with the testimony of the wise. Before about 1650, seeing ourselves as stationary and the sun and moving, made sense, it felt right, it accorded with experience, and it accorded with the testimony of the wise. The first hint that the sunset illusion is an illusion came when Galileo discovered the moons of Jupiter in January 1610.

Even knowing, as I do, that the sunset illusion is an illusion, doesn't change how it seems to me because my motion senses are unanimously telling me I'm at rest. This is important because it tells us that this is not a trivial or superficial mistake. It's not because I am too stupid to understand the situation. I know the truth and have known for decades. But I also trust my senses because I have no choice but to trust them.

The sunset illusion is sometimes presented as a 50:50 proposition, like one of those famous optical illusions where whether we see a rabbit or a duck depends on where we focus. The assertion is that we might just as easily see the sun as still and us moving. This is erroneous. Proprioception, kinesthesia, the vestibular organ, and sight make it a virtual certainty that we experience ourselves at rest and conclude that the sun moving. It takes a combination of careful observation of the visible planets and an excellent understanding of geometry to upset the earth-centric universe. If some ancient cultures got this right, it was a fluke.

The sunset illusion exposes an important truth about how all of us understand the world based on experience. Experience and reality can be at odds.

And note that we are not being irrational when we continue to refer to the sun "setting". Given our sensorium, it is rational to think of ourselves at rest and the sun moving. It's only in a much bigger, non-experiential framework that the concept becomes irrational. For most of us, the facts of cosmology are abstract; i.e., they exist as concepts divorced from experience. Evolution has predisposed us to trust experience above abstract facts.

Mind Projection Fallacy

The name of this fallacy was coined by physicist and philosopher E.T. Jaynes (1989). He defined it like this:
One asserts that the creations of [their] own imagination are real properties of Nature, and thus, in effect, projects [their] own thoughts out onto Nature. (1989: 2)
I think it's probably more accurately described as a cognitive bias, but "fallacy" is the standard term. Also, instead of imagination, I would argue that we should say "interpretation". The problem is not so much that we imagine things and pretend they are real, though this does happen, but that we have experiences and interpret them as relating directly to reality (naïve realism).

The sunset illusion tells us that reality is not always as we experience it. 

We all make mistakes, particularly these kinds of cognitive mistakes. We actually evolved in such a way as to make these kinds of mistakes inevitable. However, reading up on cognitive bias, I was struck by how some of the authors slanted their presentation of the material to belittle people. I don't think this is helpful. Our minds are honed by evolution for survival a particular kind of environment, but almost none of us live in that environment any more. So if we are error-prone, it is because our skill-set is not optimised for the lifestyles we've chosen to live. 

This fallacy can occur in a positive and a negative sense, so that it can be stated in two different ways:
  1. My interpretation of experience → real property of nature
  2. My own ignorance → nature is indeterminate
David Chapman has pointed out that there has been considerable criticism of Jaynes' approach in the article I'm citing and has summarised why. He suggests, ironically, that Jaynes suffered from the second kind of mind projection fallacy when it came to logic and probability. But the details of that argument about logic and probability are not relevant to the issue I'm addressing in this essay. It's the fallacy or bias that concerns us here. 

Interpreting Experience
    A problem like the sunset illusion emerges when we make inferences about reality based on interpreting our experience. For example, when we make deductions from experience to reality, they invariably reflect the content of our presuppositions about reality. For example, a given for most of us is "I always know when I am moving". In the sunset illusion, I know I am at rest because motions sensors and vision confirm that it is so. The experience is conclusive: it must be the sun must be moving. My understanding of how the universe works and my understanding of my own situation as regards movement are givens in this case. We don't consciously reference them, but they predetermine the outcome of deductive reasoning. This means the deduction is of very limited use to the individual thinking about reality.

    If I watch a dozen sunsets and they all have this same character, then I can generalise from this (inductive reasoning) that the sun regularly rises, travels in an (apparent) arc across the sky and sets. All the while, I am not moving relative to earth. What's more, I've experienced dozens of earthquakes in my lifetime, so I also know what it is like when the earth does move! From my experiential perspective, the earth does not move, but the sun does move. Given our experience of the situation, this is the most likely explanation (abductive reasoning).

    So here we see that a perfectly logical set of conclusions, generalisations, and explanations follow from interpreting experience, which are, nonetheless, completely wrong. I am not at rest, but moving at Mach 1.5. The earth is not at rest. The sun is at the centre of our orbit around it, but it also is moving very rapidly around the centre of the galaxy. Our galaxy is accelerating away from all other galaxies. The error occurs because our senses evolved to help us navigate through woodlands, in and out of trees, and swimming in water. And we're pretty good at this. When it comes to inferring knowledge about the cosmos, human senses are the wrong tool to start with!

    A common experience for Buddhists is to have a vision of a Buddha during meditation. And it is common enough for that vision to be taken as proof that Buddhas exist. But think about it. A person is sitting alone in a suburban room, their eyes are closed, their attention withdrawn from the world of the senses, they've attenuated their sense experience to focus on just one sensation and have focussed their attention on it. They undergo a self-imposed sensory deprivation. They've also spent a few years intensively reading books on Buddhism, looking at Buddhist art, thinking about Buddhas, and discussing Buddhas with other Buddhists. We know that sensory deprivation causes hallucinations. And someone saturated in the imagery of Buddha is more likely to hallucinate a Buddha. This is no surprise. But does it really tell us that Buddhas exist independently of our minds, or does it just tell us that in situations of sensory deprivation Buddhists hallucinate Buddhas? 

    The Buddhist who has the hallucination feels that this is a sign; it feels important, meaningful, and perhaps even numinous (in the sense that they felt they were in the presence of some otherworldly puissance). They are immersed in Buddhist rhetoric and imagery, as are all of their friends. As I have observed before, hallucinations are stigmatised, whereas visions are valorised. So if you see something that no one else sees, then your social milieu and your social intelligence will dictate how you interpret and present the experience. If you mention to your comrades in religion that you saw a Buddha in your meditation, you are likely to get a pat on the back and congratulations. It will be judged an auspicious sign. And all those people who haven't had "visions" will be quietly envious. If you mention it to your physician, they may well become concerned that you have suffered a psychotic episode. On the other hand, in practice, psychotic episodes are rather terrifying and chaotic, and not all hallucinations are the result of psychosis. 

    Not only do we have the problem of our own reasoning leading us to erroneous inferences, we have social mechanisms to reinforce particular interpretations of experience, especially in the case of our religiously inspired inferences. Our individual experience is geared towards a social reality. One of the faults of humans thinking about reality is to think that reality somehow reflects our social world. A common example is the nature of heaven. Many cultures see heaven as an idealised form of their own social customs, usually with the slant towards male experiences and narratives. Medieval Chinese intellectuals saw heaven as an idealised Confucian bureaucracy, for example. If we take Christian art as any indication, then Heaven is an all male club. The just-world fallacy probably comes about because we expect the world to conform to our social norms in which each member is responsive to the others in a hierarchy where normative behaviour is rewarded and transgressive behaviour is punished.

    So, given the way our senses work, given the pitfalls of cognitive bias and logical fallacies, given the pressure to conform to social norms, the mind projection fallacy can operate freely. As we know, challenging the established order can be difficult to the point of being fatal. And understanding the power of something like the sunset illusion is important. Facts don't necessarily break the spell. Yes, we know the earth orbits the sun. But standing on a hill watching the sunset, that is just not how we experience it (our proprioception and vision tell us a different story that we find more intuitive and credible, even though it is wrong). And this applies to a very wide range of situations where we are reasoning from experience to reality.

    If I Don't Understand It...

    The second form of this fallacy was rampant in 19th century scholarship. In the first form, one erroneously concludes that one understands something and projects private experience as public reality. Mistaking the sunset as resulting from the movement of the sun, because our bodies tell us that we are at rest. This leads to false claims about reality.

    In the second case there is also a false claim about reality, but in this case it emerges from a failure to understand and the assumption that this is because the experience or feature of reality cannot be understood. This is a problem which is particularly acute for intellectuals. Intellectuals are often over‑confident about their ability to understand everything. These days it is less plausible, but 150 years ago it was plausible for one intellectual to be well informed about more or less every field of human knowledge. So, if such an intellectual comes across something they don't understand, then they deduce that it cannot be understood by anyone. 

    A common assertion, for example, is that we will never understand consciousness from a third person perspective (leaving aside the problematic abstraction for a moment). Very often such theories are rooted in an ontological mind/body dualism, which may or may not be acknowledged. Many Buddhists who are interested in the philosophy of mind, for example, cannot imagine that we will ever understand conscious states through scientific methods. They argue that no amount of research will ever help us understand. So they don't follow research into the mind and don't see any progress in this area. On the other hand, they hold that through mediation we do come to understand conscious states and the nature of them. Many go far beyond this and claim that we will gain knowledge of reality, in the sense of a transcendent ideal reality that underlies the apparent reality that our senses inform us about. In other words, meditation takes us beyond phenomena to noumena

    Another common argument is that scientists don't understand 95% of the world because they don't understand dark matter and dark energy. People take this to mean that scientists don't understand 95% of what goes on here on earth. But this is simply not true. Scale is important, and being ignorant at one scale (the scale that effects galaxies and larger structures) does not mean that we don't understand plate tectonics, the water cycle, or cell metabolism, at least in principle. The popular view of science often seem to point towards a caricature that owes more to the 19th century than the 21st. Criticism of science often goes along with an anti-science orientation and very little education in the sciences. 

    The basic confusion in both cases is mistaking what seem obvious to us, for what must be the case for everyone else, either positively or negatively. 

    The Confusion
    "It's not that one gains insight into reality, but that one stops mistaking one's experience for reality"
    The basic problem here is a confusion between what we know about the world (epistemology) with what the world is (ontology). In short, we mistake experience for reality. And this problem is very widespread amongst intellectuals in many fields.

    The problem can be very subtle. Another illuminating example is the idea that sugar is sweet. We might feel that a statement like "sugar is sweet" is straightforward. Usually, no one is going to argue with this, because the association between sugar and sweetness is so self-evident. But the statement it is false. Sugar is not sweet. Sugar is a stimulus for the receptors on our tongues that register as "sweet". We experience the sensation sweet whenever we encounter molecules that bind with these receptors. But sweet is an experience. It does not exist out in the world, but only in our own conscious states. Sugar is not sweet. Sugar is one of many substances that cause us to experience sweet when they come into contact with the appropriate receptors on our tongue. Equally, there is no abstract quality of sweet-ness, despite the effortless ease with which we can create abstract nouns in English. Sucrose, for example has nothing much in common with aspartame at a chemical level. And yet both stimulate the experience of sweet. Indeed, aspartame is experienced as approximately 200 times as sweet as sucrose, but this does not mean that it contains 200 times more sweetness. There is no sweet-ness. The experience of sweet evolved to alert us to the high calorific value of certain types of foods and the enjoyable qualities of sweet evolved to motivate us to seek out such foods. 

    For Buddhists, the application of this fallacy comes from experiencing altered states of mind in and out of meditation. Meditators may experience altered states of mind that they judge to be more real than other kinds of states, causing them to divide phenomena into more real and less real. And they manage to convince people that this experience of theirs reflects a reality that ordinary mortals cannot see -- a transcendent reality that is obscured from ordinary people. 

    The problem is that an experience is a mental state; and a mental state is just a mental state. No matter how vivid or transformative the experience was, we must be careful when reasoning from private experiences (epistemology) to public reality (ontology) because we usually get this wrong. I've covered this in many essays, including Origin of the Idea of the Soul (11 Nov 2011) and
     Why Are Karma and Rebirth (Still) Plausible (for Many People)? (15 Aug 2015), etc.

    Most of us are really quite bad at reasoning on our own. This is because humans suffer from an inordinate number of cognitive biases and easily fall into logical fallacies. There are dozens of each and, without special training and a helpful context, we naturally and almost inevitably fall into irrational patterns of thought. The trouble is that we too often face situations where there is too much information and we cannot decide what is salient; or there is too little information and we want to fill the gaps. 

    Our minds are optimised for survival in low-tech hunter-gatherer situations, not for sophisticated reasoning. The mind helps us make the right hunting and gathering decisions, but in most cases it's just not that good at abstract logic or reasoning. Of course, some individuals and groups are good at it. Those who are good at it have convinced us that it is the most important thing in the world. But, again, this is probably just a cognitive bias on their part. 


    The whole concept of reason and the processes of reasoning are going through a reassessment right now. This is because it has become clear that very few people do well at abstract reasoning. Most of the time, we do not reason, but rely on shortcuts known as cognitive biases. A lot of the time our reasoning is flawed by logical fallacies. Additionally, we are discovering that most mammals and birds are capable of reasoning to some extent. 

    In this essay, I have highlighted a particular problem in which one mistakes experience for reality. Using examples (sunset, visions, sweetness) I showed how such mistakes come about. Unlike others who highlight these errors, I have tried to avoid the implication that humans are thereby stupid. For example, I see the sunset illusion because my senses are telling me that I am definitely at rest, because they tune out sensations that are too small to affect my body. Social conditioning is a powerful shaping force in our lives, and visions are valuable social currency in a religious milieu.

    In terms of our daily lives the sunset illusion or the sweetness illusion hardly matter. It's not like the mistakes cost us anything. Such problems don't figure in natural selection because our lives don't depend on them. We know what we need to know to survive. Although our senses and minds are tuned to survival in pre-civilisation environments, we are often able to co-opt abilities evolved for one purpose to another one. 

    But truth does matter. For example, when one group claims authority and hegemony based on their interpretation of experience, then one way to undermine them is to point out falsehoods and mistakes. When the Roman Church in Europe was shown to be demonstrably wrong about the universe, the greater portion of their power seeped away into the hands of the Lords Temporal, and then into the hands of captains of industry. For ordinary people, this led to more autonomy and better standards of living (on average). Democracy is flawed, but it is better than feudalism backed by authoritarian religion.

    But as Noam Chomsky has said:
    “The system protects itself with indignation against a challenge to deceit in the service of power, and the very idea of subjecting the ideological system to rational inquiry elicits incomprehension or outrage, though it is often masked in other terms.”
    In subjecting Buddhism to rational inquiry, I do often elicit incomprehension or outrage. And sometimes it's not masked at all. There are certainly Buddhists on the internet who see me as an enemy of the Dharma, as trying to do harm to Buddhism. As I understand my own motivations, my main concern is to recast buddhism for the future. I think the urge of the early British Buddhists to modernise Buddhism and, particularly, to bring it into line with rationality was a sensible one. However, as our understanding of rationality changes so Buddhism will have to adapt to continue being thought of as rational. But also we have to move beyond taking Buddhism on its own terms and to consider the wider world of knowledge. The laws of nature apply in all cases.

    Whilst Buddhism is largely influenced by people who mistake experience for reality, Buddhism will be hindered in its spread and development. This particular error is one that we have to make conscious and question closely. Just because it makes sense, feels right, and accords with experience doesn't mean that it is true. The sunset illusion makes sense, but is wrong. It feels right to say that sugar is sweet, but it isn't. It accords with experience that meditative mental states are more real than normal waking states. But they are not. The testimony of the wise is demonstrably a product of culture, and varies across time and space.


    23 October 2015

    Reality. Again.

    There's a lot of talk about reality in Buddhism. Buddhists will often claim that our meditations will give a person direct access to reality, or knowledge of reality. I've come to see that these claims are bunk. Part of the problem is that our Iron Age predecessors introduced a term yathābhūta-ñāṇadassana which is taken to mean "knowledge and vision of things as they are". Now these Iron Age predecessors were not seeking knowledge of reality by any definition of that word that might be relevant to a modern reader. They sought knowledge of the origins and ending of suffering, where suffering was primarily experienced through repeated rebirth into the world. They claimed to have knowledge of how the rebirth process works and the conditions which lead to suffering. At no point do they claim knowledge of reality as we understand that term.

    One of the problems we have in the philosophy of science is that classical mechanics is a description of reality as we experience it, but quantum mechanics is not a description of any reality we could experience. Of course we can experience the classical consequences of quantum phenomena - the scattering pattern of the two-slit experiment, for example, is a classical consequence of the quantum phenomenon. But we do not experience the phenomenon inferred by quantum mechanics (a photon passing through both slits simultaneously and interfering with itself). All the clever people do is work out mathematically how to make the same result appear in their calculations. Sure the calculations are accurate, but they have an entirely uncertain relationship to reality. Given that we have an equation that is accurate at predicting the classical consequences of quantum phenomenon, it is tempting to think we have a map of some hidden territory. But nothing could be less certain than this conclusion. No one understands the reality that quantum mechanics describes, however, good they are at fiddling with the parameters to create classical consequences. Reality at that level is a black box and likely to remain so forever. 

    We have much the same problem with General Relativity. These days we wonder how stupid people must have been to think that the sun goes around the earth. But just by looking at the sun it is very difficult indeed to  see this. The ending of the geocentric worldview was not brought about by insights into the sun, but into the planets. It was understanding that the planets were not in orbit around the earth, but around the sun that made us question the geocentric model. General Relativity tells us that there really is no force of gravity. The reality is that masses cause spacetime to curve in around them. We know from Newton that masses travel in a straight line unless some force acts upon them (from the First Law of Motion). So when we see an object moving in a curved path we naturally conclude that some force is acting on it. If we throw a ball it travels in a curve (a specific kind of curve known as a parabola) and falls to the earth. As one of my Buddhist teachers once said at a public meeting "Gravity is a larger mass attracting a smaller one". That's completely wrong of course and attracted gasps of horror from the Cambridge audience (there was more than one physics PhD in the room!). But that does describe the experience. Two tennis balls don't attract each other the way that the earth and a tennis ball do. The fact that the earth moves an infinitesimal amount towards the tennis ball is obscure because the effect is too small for us to measure, let alone see. Experience suggests that objects are attracted to the earth in a way that they are not attracted to each other. 

    That's just how it seems. But it is not the case at all. A very cleverly designed experiment in Cambridge's Cavendish laboratory showed that small masses do appear to attract each other gravitationally, but that the apparent force is very tiny because the masses involved are so small. Even so all this is incidental because Einstein's theory tells a different story. General Relativity tells us that the reason the ball follows a curved path is that spacetime is strongly curved near the surface of the earth. The ball is doing it's best to obey Newton's First Law of Motion and travel in a straight-line. What it "discovers" is that there are no straight lines near the earth. So the ball follows the curvature of spacetime which happens to be in the shape of a parabola. 

    Try as we might we cannot see spacetime. We know it must exist precisely because of things like light propagating through space, and the path of light being bent near masses (light is itself massless so there is no possibility of a gravitational interaction). There is an enormous body of evidence which makes us quite certain that we have understood spacetime under normal circumstances. However, the theory itself must be incomplete because it breaks down at the Big Bang. The maths says that at the Big Bang, the dimensions of spacetime were all zero; implying infinite density. My many physics teachers over the years always emphasised that when your calculation produces an infinity, then you have done something wrong and must go back and check your working. Reality does not contain infinities, or if it did then everything would be incomprehensible different than it is. Either way we do not understand the Big Bang because it involves infinity. 

    No amount of mediation and insight is going to directly help us with these problems. One can imagine that meditation and insight might help a physicist or mathematician in their work, but, on the whole, the two projects are completely unrelated. The experience of rarefied mental states does not shed light on reality. So what does it shed light on? Experience. It ought to come as no surprise that what we gain insight into when we examine our experience, is experience itself. I'm more and more convinced that specific types of meditative experiences are what the Buddhists were aiming at. They come under the broad heading of emptiness. Of course, there are many kinds of experience that one can have in meditation. Some of incidental or spurious and others profound. But in terms of the liberating insights said to end rebirth or being (bhava) I am beginning to focus my attention on those states in which there is no content: so sense experience and no normal mental experience, and yet still some kind of experience. I first noticed this in 2008 in an essay called Communicating the Dharma:

    Further there are sensations associated with desire (chanda), thinking (vitakka) and with the perceptions (saññā). Sensations are present in all the combinations of presence or absence of these three. When they are all absent something new arises that is simply described as stretching out for (āyāmaṃ) the attainment of the as-yet unattained (appattassa pattiyā), and finally there are sensations associated with this.
    It is in these states of emptiness that one has a kind of transformative experience that reorganises the psyche and the relationship with sensory experiences. From the same essay:
    The Buddha here is saying something quite profound - that if one looks beyond mundane everyday experiences, if one can put aside desire, intellectual twisting and turning, if one reaches beyond the normal scope of consciousness - then one finds not annihilation, but something as yet unattained. 
    And I think it is this kind of experience that is being described or discussed in the Perfection of Wisdom texts. Consider for example this abstruse discussion between Subhuti and Śāriputra from the first chapter of the Aṣṭasāhasrikā-prajñāpāramitā (Chp1, para 7, my translation.)
    Then indeed, Elder Śāriputra said this to Elder Subhūti, “Still, Elder Subhūti, does that mind which is without mind, exist?” 
    That said, Elder Subhūti said this to Elder Śāriputra, “With respect to a state of being without mind (acittatā) can existence (astitā) or non-existence (nāstitā) be found or obtained?”
    Sāriputra said, “This is not [the case], Elder Subhūti!” 
    Subhūti said, “If, Elder Śāriputra, existence or non-existence are not found or obtained there in the state of being without mind, is the question, 'Does that mind which is without mind, exist?' appropriate for you Elder Śāriputra?”
    When that was said, Elder Śāriputra said this to Elder Subhūti, “So what is this state of being without mind, Elder Subhūti?” 
    Subhūti said, “Śāriputra, the state of being without mind (acittatā) is immutable (avikāra), does not falsely distinguish (avikalpa)  [between real and unreal].
    This is one of several passages in the Aṣṭa that are reminiscent of the Kaccānagotta Sutta (SN 12.15) in denying the applicability of the ideas of existence & non-existent or real & unreal in discussions about Buddhism. These concepts do not apply to the world of experience.

    Following D T Suzuki and Edward Conze, we usually take this kind of self-negating language in the Perfection of Wisdom texts to be an attempt to confuse the rational mind in accordance with Romantic anti-intellectualism. Romantics believe that ultimate truth comes rather from the inner spirit than from the intellect. The idea here is that by tying the rational mind up in riddles, the spirit can assert itself. Apart from the fact that Romantics interpretations are all dualistic and eternalistic, and thus grossly false by most Buddhist standards, this procedure is akin to banging one's head against a brick wall in pursuit of wisdom. Treating the entire Prajñāpāramitā literature as a gigantic koan is simply a mistake. Just because Suzuki and Conze were confused does not mean that confusion is the only possible response to these texts. 

    On the other hand, if we assume that the context of the dialogue is two master meditators trying to articulate the experience of emptiness, in the sense of contentless meditative states, then we can stop banging our head against the wall. I don't claim to have unlocked the language of the text, but I am hopeful that abandoning Conze's awful translation and re-reading the text as though it makes sense will be fruitful. Compare this to my comments on Paul Harrison's work on the comprehensibility of the Vajracchedikā-prajñāpāramitā. Part of my optimism stems from several essays written about emptiness by my colleagues in the Triratna Order, one of which is available for public consumption (the others are embargoed as they are part of an in-house discussion in the Order, I am trying to encourage my colleagues to make their work more widely available). Satyadhana's essay The Shorter Discourse on Emptiness (Cūḷasuññatasutta, Majjhima-nikāya 121): Translation and Commentary, in the Western Buddhist Review, gives us a flavour of the discussion. It seems to me that there are important continuities that have yet to be explored, but which promise to shed a great deal of light on the intentions of the Prajñāpāramitā authors.

    Buddhists often assume that because Quantum Mechanics and Emptiness are both confusing and reputedly profound, that one must shed light on the other. I've done my best to debunk this fallacy in two previous essays (Erwin Schrödinger Didn't Have a Cat and Buddhism and the Observer Effect in Quantum Mechanics). The reality that we struggle to understand through the abstruse mathematics is not the same as the reality that we seek to understand through religious exercises. The mistake seems to rest on a misunderstanding of what the word "reality" means. Scientists and meditators use the word in ways that are almost entirely unrelated.


    This essay is partly inspired by a series of essays on the blog a filosofer's thots, starting here: Bohr’s reply to EPR (Part I) spotted in the Twitter feed of @seancarroll.

    17 April 2015


    Reality is a slippery concept. I hesitate to even mention it. Science fiction author Philip K Dick said, "reality is that which, when you stop believing in it, doesn't go away". Reality is that which has the quality of being real. However, "real" is only ever defined circularly. Real is actual, existent, true: each of these words defines the others. The word comes from Latin res, but this word has an uncertain origin. I'm going to try to avoid scare quotes, but in fact if any words deserves them all the time, then real and reality do. 

    This essay will look at reality by beginning with experiences that people would say are not real. This is also an awkward proposition. The unreal experience can seem to be real, can seem to be more real than real. Aren't we always in the position of the Zen master who could not tell if he was a man dreaming he was a butterfly, or a butterfly dreaming he was a man? And what do I mean when I emphasise that an experience is real or unreal as opposed to saying that we have an experience of something that is real? Can we have real experiences of unreal objects? Or vice versa? With these questions in mind, let's begin with hallucinations!


    What is an hallucination? At first, in the early 16th century, the word just referred to a wandering mind. Only in 1830 did French psychiatrist Jean-Étienne Esquirol use it to refer to what until then might have been called "apparitions". An hallucination is, generally speaking, a perception arising in the absence of any external stimulus. But crucially what distinguishes an hallucination from a misperception or imagination is that we believe that the perception does arise from an external stimulus. By this definition, hallucinations are difficult to distinguish from dreams. The world we interact with in dreams does seem external to us. However, except for a few strange circumstances, which we'll mention below, dreams only occur while we are asleep. Hallucinations are waking experiences. It is of course possible to mistake one state for the other, but seldom for long. If one resists the "Guru Effect", the Zen master sounds confused rather than profound.

    Hallucinations occur across all the sensory modes of the human sensorium, though visual and auditory hallucinations are by far the most common. Very often hallucinations take on a human form. When we see things that are not there, we often see faces (see also the phenomenon called pareidolia), or people; when we hear things we hear voices or music. Another common hallucination is to feel the presence of another person. Hallucinatory perceptions vary in their clarity and intensity. Some are merely vague feelings, such as an indefinable sense of dread before a migraine attack for example. Other hallucinations seem as real as reality, or in other words are indistinguishable from reality and there is nothing to alert us that we are not simply experiencing what is there. At other times hallucinations can be preternaturally vivid and hyper-real. We may see colours more vivid than any in reality, like a heavily saturated or "high dynamic range" photograph; or we may see colours which seem not to have any real world analogue (and after all Newton invented the colour indigo when he named the colours of the rainbow). The level of similarity to reality has a huge influence on how we interpret hallucinations, but before going further into this topic, we need to say something about the circumstances under which we have hallucinations.


    Because of taboos surrounding hallucinations they tend to be under reported. In the infamous Rosenhan experiment several researchers presented themselves at psychiatric hospitals and said that they had heard a voice say to them "a resounding thud", but had not heard any voices since. They did not feign any other psychiatric symptoms. But all were diagnosed with a serious mental disorder, usually schizophrenia, prescribed antipsychotic medications and hospitalised for a period of some weeks. We fear being judged mad if we admit to perceiving things that aren't there, except under special circumstances that I will outline in due course.

    Hallucinations may occur with sudden loss of sight or hearing. In Charles Bonnet Syndrome for example those who lose their sight hallucinate people that move around but do not interact with them. The hallucinations are compelling at first, but the sufferer usually realises quite quickly that they are not real. Phantom limb pain is an hallucination associated with loss of a limb and the felt sensations associated with it. Though some people born without limbs, due to birth defects, may also feel phantom limbs. Nor need the loss of sensory perception be organic. Spending time in a sensory deprivation chamber can also stimulate hallucinations. It is quite common to experience auditory hallucinations in anechoic chambers (spaces which do not reflect sound). Some types of meditation involve training the mind to withdraw attention from the senses and this may elicit the "visions" that some people have in concentrated states.

    Many hallucinations are caused by an illness of some kind. People with Parkinson's Disease can have hallucinations associated with taking the medicine L-dopa. People who suffer from epilepsy can have a wide range of hallucinations. Migraine suffers regularly have distorted sense perception before the onset of headaches, and this very often involves so-called auras - lights in the visual field, often in characteristic zigzag patterns. Some however have more drastic symptoms. It is thought by some that Lewis Carroll suffered from migraine and some of the visionary aspects of his Alice in Wonderland stories are attributable to his hallucinations. People who have high fevers frequently hallucinate, as do those with extreme starvation or dehydration. The austerities pursued by various religious orders often involve extreme physical stress designed to bring on 'visions'. Other kinds of stress or shock can also result in hallucinations, from the intrusive memories of Post Traumatic Stress Disorder to the very commonly felt presence of a loved one after they die. One study of the latter suggested that 50% of people felt the physical presence of the deceased, sometimes for weeks after the death. Stressful situations, such as accidents or surgery, can cause the common hallucination of being outside one's body. The so-called out of body experience is quite well studied. Another common category of hallucinations is the near death experience. These are less well studied in the sense of the mechanisms involved, but many of the narrative interpretations have been collected and published.

    The other most obvious source for hallucination is altered states. Many drugs produce hallucinations and there are instances of humans using hallucinogens throughout recorded history and evidence stretching back into pre-history. Excessive use of a drug like alcohol can produce hallucinations, when moderate doses do not. Similarly suddenly stopping some drugs after heavy use can cause hallucinations. However there are other ways to disrupt the brain. We've already mentioned fever for example. Nowadays magnetic or electrical stimulation  have are used to disrupt brain functioning, sometimes producing hallucinations. Meditation is another way to get into an altered state, and as we've mentioned many people have hallucinations while meditating.

    A major source of hallucinations is associated with sleep. These occur when dream states blend into waking states. Sleep related hallucinations may be hypnagogic or hypnopompic. The former occur in the transition from wakefulness to sleep, while the latter occur when going from sleep to wakefulness, though the distinction seems mostly semantic. One of the most common hypnopompic hallucinations is associated with sleep paralysis. While in a dream state the body is usually prevented from moving by a reflex - presumably it evolved to stop us falling out of trees when we dreamed. This is reflex is relaxed in sleep walking. In a classic sleep paralysis "nightmare" one wakes, but is unable to move or speak. And one feels the presence of someone or some thing. Very often because of being unable to move this feeling is accompanied by fear or even panic as the presence seem malevolent. Other kinds of dream type imagery can invade the waking state as well, especially with prolonged sleep deprivation.

    Clearly there is a lot of scope for hallucinating and it seems likely that everyone experiences hallucinations at one time or another, without any suggestion of psychosis or mental ill-health. How we interpret these experiences seems to depend on a complex mix of factors including culture, religion, and the specific circumstances.

    Interpreting Hallucinations.

    Clearly from the medical perspective some hallucinations have valuable diagnostic value. If I have the visual disturbances typical of migraine then my doctor can make the appropriate diagnosis and recommend I avoid those foods known to trigger migraines and take specific medications either to prevent or mitigate them. Hallucinations make help to locate a brain tumour by their specific content - visual hallucinations might be caused by a tumour in the visual centre for example. Similarly for seizures. Persistently hearing voices may be a sign of psychosis (though many people who hear voices are not psychotic). And so on.

    But the medical interpretation has its limitation both in applicability and attractiveness. For those who are not ill, the significance of their hallucination may range from a trivial annoyance, right up to a revelation from God. When hallucinations are particularly vivid or accompanied by feelings of bliss or well-being this might be more easily understood in religious terms. Hallucinations can be interpreted as windows onto another reality. The other reality may in fact seem more real than reality (hallucinations may appear hyper-real). 

    How we interpret an hallucination will depend to some extent on how we think our testimony will be received. If I tell a doctor I hallucinated voices, I will most likely be diagnosed with some psychopathology or physical illness. If I tell my Buddhist friends I had a vision of the Buddha, I'll be encouraged and perhaps celebrated (my Buddhist Teacher's visions are celebrated as evidence of his holiness by some of his disciples). On the other hand, the person who believes that God speaks to them or that they were abducted by aliens is frequently a figure of fun.

    However, we run into problems when we interpret private experience as public reality. When we extrapolate from private experience to public ontology we almost inevitably go astray. 

    Towards Definitions of Realities

    What hallucinations and other misperceptions show is that definitions of reality that depend on individual perceptions are weak because an individual can easily be fooled into perceiving things are we would not consider real. This points to the need for definitions of reality that are based on commonality. Indeed there seem to be two approaches to defining reality.

    The first approach we can call "consensus reality". The image accompanying this essay is of a small blue glass sphere I've owned for many years. Most people, unless they are trained to think differently, are naive Realists. If I was a naive Realist I would take the perception of my blue glass sphere on face value. I would take my experience for reality. This approximation turns out to be a workable rule of thumb. Reality must be not too different from how we perceive it to be, or we would be constantly banging into things, falling over and getting lost. And in fact most of the time we avoid obstacles, stay on our feet, and navigate to the supermarket and back home without much trouble. Clearly the match is not perfect because sometimes our perceptions do mislead us, but most of the time we do pretty well.  I can toss my glass sphere from hand to hand quite easily and accurately (if I had three I could juggle them). For most people being a naive Realist is no great disadvantage. Now, when a bunch of naive Realists get together, because their maps of the world are pretty accurate, they can get a high degree of consensus about what the world is like, at least on a physical level. This is what I would call "consensus reality". It's real in the sense that it provides an accurate model for navigating the world. I'm not a believer in absolute reality in any case, but this consensus reality is contingent and relative. 

    Things get more complicated if we are talking about culture - economics and politics are quite difficult to get agreement on. Britons are about to have a general election. Clearly public opinion is deeply divided in Britain at the moment. The likelihood is that no one party will have a majority in the House of Commons. Thus arguments about policies take on an added verve. Should we continue to have austerity in preference to all other economic approaches? Does it ring true that the proponents of austerity are currently throwing out uncosted election bribes every day, all of which contradict their so-called long term economic plan? Is Labour a credible alternative for those who want to remove the Tories from power? Does the fact that the former left-wing party now espouses Neoliberal economic policy put off traditional voters, or has everyone bought the Neoliberal propaganda? Given that no party will have a majority, what shape will the government take? Generally speaking once humans are involved then things get messy. Reality in this sense is more difficult to define. 

    A feature of consensus reality is that it can be parasitised by beliefs that are based on psychological imperatives. For example almost all humans believe in life after death, not because they see regularly see people coming back to life, but because it seems preferable to the alternative (on the basis of this belief, some people have gone looking for evidence, but they set the evidentiary bar pretty low and suffer from strong confirmation bias). That said, belief in an afterlife is not trivial. People kill and die for their version of the afterlife; they create oppressive living conditions for themselves and others to try to ensure a good afterlife. The necessity of suffering in life is something that falls out of the metaphors we use to define the matter/spirit dichotomy (see Metaphors and Materialism).

    The contingency of consensus reality is what makes it unsatisfactory, especially in an age where empiricism has lent clarity and accuracy to other domains. 

    The second approach I'll call "empirical reality". If we come back to the blue glass sphere I own, and we apply scepticism and close observation we can come to somewhat different conclusions to naive Realism. Close observation for example shows that the light source and spatial relationship with the object affect how we see it. In the photo the sphere is lit from behind by an LED torch against white background. The dynamics of the camera lens and sensor, not to mention the Instagram processing, also affect how the picture comes out. We start to realise that the way the sphere looks is partly due to physical properties that are not obvious. For example, careful experimentation would show that because the glass has a high lead content (it is heavy for it's size) gives it a high refractive index compared to other transparent objects and this gives it a distinctive appearance. We might also discover that doping the glass with a small amount of some salt of copper or cobalt gives it that deep blue colour. We might discover the though it feels smooth the surface is minutely textured. And so on. 

    One of the most important features of this approach is that it relies on confirmation. An empiricist looks for repeatability before announcing their discovery. And it is only accepted by the wider community once it has been confirmed by other empiricists. This is why the announcing of one-off results to the news media is so irksome to serious scientists - it undermines the process and since one-offs often turn out to be anomalies, it casts unnecessary doubt on empiricism as a method. Careful empiricism is the most successful knowledge generating activity we've ever known. It has transformed our understanding of the world and our place in it, though often with unforeseen consequences. Empirical reality is also less liable to parasitisation by beliefs. Empiricism has antibodies for false beliefs. False beliefs do sometimes take hold, but the practitioners of empiricism are motivated in various ways to disprove current beliefs and so false beliefs get rooted out eventually. 

    What empiricism shows us is that although consensus reality is OK to be getting on with, there is a deeper reality, or perhaps that a deeper understanding of reality is possible. And over some centuries what we discover is that reality seems to have many such layers. Naive Realism is accurate enough on the human scale. But at the nano level we can talk about atoms and molecules to give a much more accurate picture. Atomic theory allows us to manipulate materials and invent new ones with great precision. On the appropriate scale atoms are real, it's just that on much smaller scales or at energy levels sufficient to break the atom into its constituent parts we find that a more accurate description involves sub-atomic particles. At a deeper level these particles are made up from quarks. And beyond that we think in terms of fields, which may well be the smallest scale reality in our universe. Going in the other direct we find that we can describe the universe pretty well until we start dealing with very large masses or very high velocities, then we must use relativistic descriptions to predict how matter will behave. 

    Compared to consensus reality we may call these deeper realities, "empirical realities". The plural must apply because at the appropriate scales of mass, energy and length, for all intents and purposes they are real. For example one could never observe a quark in a kilogram of matter, taking up 1000cm3 of space, at 20°C. Quarks don't really exist as separate entities under these conditions. To get any evidence of quarks at all we have to change these conditions by many orders of magnitude, i.e. to smash single protons together at close to the speed of light and observe the decay products. It may be that the Standard Model of physics is accurate enough for most purposes, but we know that it cannot hold at time = 0 in the universe because it implies infinities that are impossible. Those infinities tell us that something else is going on at the moment of the Big Bang, something we have yet to understand, though there are several plausible conjectures being explored at present. 

    All Together Now.

    So is there are ultimate reality? It may be that there is, but as far as I know we've not found it yet, nor any evidence for it. Reality depends to some extent who is looking, what they are looking for, and how they look. The idea that there is one reality and that all else is unreal is a dichotomy driven by theological legacies that I would trace back to monotheism. Monotheism creates all or nothing situations. Either you believe in the one god or you don't. Traditionally you are either for god or against; destined for heaven or for hell. It's a hermeneutic that pervades the minds of those whose cultures are now, or were until recently, in the grip of monotheistic religions.  

    So is my blue glass sphere real? If I threw it at your head you would certainly know it. It's dense and heavy enough that it would probably injure you. Thrown hard it might well kill you. That suggests a certain level of reality. Several times I've sat it on a table and asked a group to describe it. I've found that they all agree that it has certain physical qualities (spherical, blue, cool to touch etc). If it wasn't real at some level, then how would a group of people agree on it's description? If the qualities were not intrinsic to the object then how could multiple sensing subjects perceive the same qualities? If the object itself was not coordinating the shared perception by having intrinsic properties, we'd have to invent some other entity or force to explain the coincidence of perceptions. And that other coordinator would never be as simple or plausible as a real object.

    Common or shared perceptions are typically left out of arguments about reality, especially by Buddhists. Buddhists will go to extraordinary lengths to assert that everything is connected, but then argue about perception as though there is only one person in the world. This is similar to the simplifying assumptions that macro-economists make so that they can use micro-economic concepts like supply and demand. Macro-models of supply and demand literally make the assumption that there is only one consumer and one product, selling for one price. In any other field, except Buddhism or economics, a requirement for an assumption as gross as this to validate the model, would contrarily be seen as falsifying the model. But all of Buddhist psychology argues as though there is a single mind, having sensory experiences one at a time, without reference to other minds.

    In the Yogācāra context we often get the example of disciples arguing over where the flag moves or the wind moves. In thinking about this we must remember that in India "wind" (vāyu) is the principle underlying all movement. The master tells the disciples, "it is your mind that moves". Which on face value sounds profound, but points to a form of unhelpful Idealism that often ties unwary Buddhists in metaphysical knots. In terms of how to do meditation this is fine. But Buddhists often take it to be statement of ontological truth. The more interesting observation, for my money, is that all the disciplines and the master are agreed that there was a flag. This simple fact is something Idealism struggles to explain. If it was the minds of disciples that were moving, then what was it made them all see a moving flag at the same time? If it was not the flag itself, then what was it?

    Of course perception is something that happens in our brains. In reality we do not see a blue sphere or a waving flag. What happens is that streams of photons are refracted, reflected, selectively transmitted and absorbed, and arrive in the retina where they are absorbed by light-sensitive cells that send electro-chemical signals to the visual centres of the brain, where a process we don't presently understand interprets the signals as shapes and colours in the world.

    By comparing notes on the same object we get information about our sensory apparatus. And by comparing notes on different objects perceived by the same subjects, we get information about objects. Empiricism from multiple points of view produces knowledge about the world that is independent of observers as well as knowledge about how the observers produce knowledge.

    However, while we can gain knowledge of the world, we have to question whether reality, in the sense of ultimate reality, is even a useful concept. We can certainly argue that atoms are more fundamental than macro-scale objects and quarks are more fundamental than atoms and fields more fundamental than quarks. But so what? We cannot normally perceive other scales and what happens on those scales does not affect our day to day decision making. Quantum mechanics is frequently invoked in this context, but quantum effects can only be observed in extremely unnatural circumstances. I can get to the supermarket and buy a loaf of bread without ever consciously invoking QM. It is true that computers have now automated the supermarket side of things, but it all worked before computers.

    In Practice

    Buddhists are often quick to point out that this kind of discussion about reality has no impact on practice. I think this is short sighted. Clarifying some of these details is vital for practice. Because at the very least it helps to clarify the object of our meditation. For example many Buddhists seem to believe that through meditation they will gain insight into ultimate reality. But thinking about reality makes this seem very unlikely. Ultimate reality is clearly not going to be understood through an individual's experience, since our ability to know anything is strictly limited. In order to have knowledge of reality as posited by Buddhists we would need a reality detecting faculty which is neither the five physical senses nor the mind. No such faculty is ever postulated by Buddhists. Nor is it conceivable. When we go back to the early Buddhist texts, they seem to agree that reality is nothing to do with the Buddhist goal. Buddhists look at and gain insight into experience rather than reality. Thus there is no need to postulate a special sense faculty required for knowledge conducive to liberation. 

    This distinction is important in focussing the mind of the meditator. If we are examining experience then that it a relatively straight-forward task, we have methods for doing so, and the process can be undertaken systematically and deliberately. However if what we are looking for is insight into the nature of reality then this cannot be undertaken systematically. Somehow reality will make itself known to us, we just have to rely on a kind of grace (I'm paraphrasing narratives I've heard my colleagues and others use). Seeking reality through meditation is a very different activity from seeking to understand experience. In fact as a passive process it can hardly be called an "activity" at all. Some schools of Buddhism completely excise the possibility of awakening-directed activity. One can only rely on external agents and forces in some forms of Pure Land Buddhism for example.

    A classic example of the difference is to be found in my forthcoming article in the Journal of the Oxford Centre for Buddhist Studies (due out in May 2015) on the first sentence of the Heart Sutra. Conze, the "modern gnostic" as he styles himself, has Avalokiteśvara floating above the world engaged in mystical practices that by mystical powers afford him insight into the reality of the skandhas. In fact, and the Chinese and Tibetan versions bear this out, what Avalokiteśvara is doing in the Sanskrit manuscripts, is examining his experience using a skandha reflection and he sees that experience is not reality at all, that experience is contingent on reality and the mind overlapping. There is of course nothing new in this observation since it pervades early Buddhist texts as well. 

    The trouble with the mystical approach is that it removes Buddhism from the human sphere. Only a few individuals will ever be blessed by insight. The rest just have to take it on faith. On the other hand, if insight arises from the deliberate and systematic examination of experience, then this is literally open to everyone. When we invoke the concept of the "nature of reality" in the Buddhism we cut most people off from the goal of liberation. And we confuse many people about what the practices are and do. So in my view this is a discussion we urgently need to have.

    One thing one often hears, especially from Baby Boomers who had access to LSD in the 1960s and 1970s (when tabs were much stronger!) is that their experience of tripping opened doors to another reality, or affected how they viewed reality. The psychedelic experience can certainly be a compelling one. But let us think for a minute what is happening. LSD is thought to interact and interfere with brain systems that use the neurotransmitter serotonin (migraine also does this). It's not that suddenly a new reality external to the mind comes into existence or that we gain access to it. This is at best a metaphor. Changes in the way the brain processes information alter the way users experience of the world. The fact that the changes feel profound is simply one of the changes. If we interpret an experience as being "profound" then the profundity is simply another aspect of experience. The sense of profundity may be ascribed an intrinsic value over and above the experience which accompanied it. But we know that a sense of profundity can be switched on and off. People with depression, another phenomenon associated with serotonin, often have the sense that nothing has meaning, that nothing is beautiful. That everything is the opposite of profound.  So too with bliss and all the other aspects of religious or mystical experiences. The mystic is not in touch with, not in, another reality. They simply interpret experience differently and it is peculiar to them (and thus fits the definition of an hallucination). In fact Aldous Huxley was right to refer to the "doors of perception" which is one way the Buddhist texts refer to the senses (i.e. indriya-dvara).

    Once I was talking to a Buddhist teacher about his experience of the breakdown of subject/object duality. For him this was a more profound experience than insight into the contingency of self. I pointed out our perceptual situation, that I was sitting facing the door and that he had his back to it. He had to admit that even with no sense of subject/object that his point of view was unchanged - he could not see the door without turning his head. Thus we have to take the "breakdown of subject/object duality" as a metaphor. It's tempting to say that his experience is subjective, but in Buddhist terms all experience is by definition both subjective and objective.

    Metzinger's model of the first-person perspective has three target properties:
    1. mineness - a sense of ownership, particularly over the body.
    2. selfhood - the sense that "I am someone", and continuity through time.
    3. centredness - the sense that "I am the centre of my own subjective self".
    As Metzinger's own work shows it is possible to interrupt these target properties and thus disrupt the first-person perspective. Meditation can do this too. But the resulting experience is not more real. It sounds as though it can be more satisfying, though of course sometimes the disruption of the first person perspective can be devastating and debilitating. In part the narratives about reality in this context are attempts to valorise experiences. By referring to religious experiences as more real, we raise the value of the experience and the charisma of the person who experienced it. In other words this kind of discourse about reality is highly motivated.

    Reality is Over-rated.

    Many religieux, especially Buddhists, seem excited by the idea that science proves their religious beliefs. Though this is usually accompanied by an excited rejection of science that disproves religious beliefs. Quantum Mechanics is invoked all too frequently - I've dealt with this fallacy on two occasions: Buddhism and the Observer Effect in Quantum Mechanics (2014) and Erwin Schrödinger Didn't Have a Cat. It reinforces the idea that religieux are only interested in proving what they believe, and not in truth per se. Religieux believe they know the truth already and simply want confirmation that they are so knowledgeable. Even if we exclude the blatantly mystical and fantastic from Buddhism, which many Western Buddhists do as a matter of course, we still find our beliefs challenged by science and even more so by history. But in fact Buddhists have no special insights into reality, let alone the nature of reality. Most of what Buddhists believe runs counter to the best explanations we have of reality. However this seems to me to be because we take insights about personal experience and try to use them as ontological theories. Buddhists are pretty good on the subject of experience. Buddhist practices are still useful for exploring experience. Used judiciously Buddhist theories are useful for understanding experience. Reality is not at all as Buddhists describe it, except that it is changeable, but then as I've said elsewhere: Everything changes, but so what?

    So it seems to me that "reality" is a concept with limited value. To some extent we do need to discuss what we can agree on and what we cannot. To some extent deeper concepts of reality enable engineers and scientists to work more efficiently. I don't need a very sophisticated concept of reality to jump on my bike and head down to the shop to buy a loaf of bread. Arguing about the inflated price of housing in the UK might take a more sophisticated version of reality, although this discussion is highly polarised because of the influence of ideologies. Making a modern computer requires a very precisely specified reality. But when it comes to religion, our ideas about reality become inflated and speculative. As far as Buddhism goes, speculation about reality seems to be a distraction, a hindrance. If we are to encourage everyone to explore their experience, which seems a laudable goal, then we need to reframe our narratives of what Buddhism is about and how it works to reflect this. 


    Further reading:

    'The brain treats real and imaginary objects in the same way'. Science Blog. 6 Mar 2015.
    Sacks, Oliver. (2012) Hallucinations. Picador.
    Cima, Rosie. 'How Culture Affects Hallucinations'. 22 Apr 2015.

    6 Jan 2015. For an interesting account of the self-induced hallucinations encountered in meditation, see:
    Eveleth, Rose. (2014). The Ancient, Peaceful Art of Self-Generated Hallucination. Nautilus, 19 Mar.