Erwin Schrödinger Didn't Have a Cat

image: Erwin Schrödinger

"Science is the belief in the ignorance of experts."
Richard Feynman. "What is Science?"
The Physics Teacher Vol. 7, issue 6 (1969)

"I think I can safely say that
nobody understands quantum mechanics."
Richard Feynman. The Character of Physical Law (1965)

~~~~

SCHRÖDINGER'S CAT is one of the most famous thought experiments in the history of science. Erwin Schrödinger (left) used it to try to argue against adopting one approach Quantum Mechanics. Most people seem unaware that he was trying to highlight a problem with what was, in 1935, a controversial theory, but which has become the orthodoxy: namely the Copenhagen Interpretation of Quantum Mechanics . These days when we say Quantum Mechanics we usually mean the Copenhagen Interpretation of Quantum Mechanics (hereafter QM). Many people who know next to nothing about science, or about Schrödinger, have tried to co-opt Schrödinger's cat to show how there is a relationship between physics and Buddhism. Let me say at the beginning that I don't believe that there is any significant cross-over between physics and Buddhism, and that I hope to explain why in the rest of this post. Granted my degree is in chemistry and it was a long time ago; but I also studied physics, and I'm an ordained Buddhist, so I feel at least not-overly-unqualified to comment.

To begin with we need to be clear on scale. An atom is between 32 picometres and 225 picometres in diameter. A picometer is 1×10⁻¹² m, i.e. a trillionth of a metre, or 0.000000000001 m. By contrast a human hair is around 50 µm or 0.000005 m. So a single hair is about about 1.5 million helium atoms in diameter. Basically this scale is unimaginable, so let's put it another way: if the diameter an atom was the thickness of a single sheet of copier paper (0.08mm) then a human hair would be 120 metres in diameter. Amedeo Avogadro showed that 12g of carbon contains approximately 6 x 10²³ atoms of carbon. That is 600,000,000,000,000,000,000,000 (600 sextillion) atoms. If each carbon atom was 1 mm³ then the 12g of carbon would fill the Western Mediterranean Ocean (from Gibraltar to Sicily), with plenty to spare. In fact 12g of carbon (in the form of powdered soot) is about 2 teaspoons. In QM we're dealing with the subatomic world, with the protons, neutrons and elections, and the weirder particles which make up atoms. A proton is about 1/50th of the diameter of the smallest atom; while an electron is thought to be in the region of 10⁻²²m, which is one 10-billionth the diameter of a proton. Don't be fooled by our ability to write these properties down in numbers: they are highly abstract, unimaginable, incomprehensible, and none of us can draw on experience to get a sense of them. If you are still confident that any of this is relevant to human existence then read on.

Those with an interest in this subject will know that QM conceives of subatomic particles as waves (which can behave like particles under some conditions) that are described not in terms of physical properties, but in mathematical formulas. QM is the first theory of science to not be based on observations of physical properties, but to emerge from abstract mathematical speculation. [ 1 ] Though of course QM makes testable predictions about the behaviour of matter on the picometer scale. This description of sub-atomic particles as waves has some interesting consequences. One is that the particle is not a point in space, but is smeared out over space. Another is that all we can know about the particles in atoms are the odds of the particle being in any one place in space at any given time. What's more, as Heisenberg showed, if we know precisely where a particle is, then we can't simultaneously know how fast it is going - this is called the Uncertainty Principle.

Schrödinger's thought experiment related to a curious prediction arising out of the mathematics of waves (subsequently experimentally confirmed). Under certain circumstances two wavy particles can become 'entangled' which means that their waves combine into a single system, though they retain their identities. (Don't worry if you don't quite understand how this works - Feynman was not being ironic when he said that no one understands QM.) Schrödinger's problem was that this meant that observing some of the properties of one of the particles, meant having certain knowledge about the other particle because the two must be in opposition. The main property we are concerned with is called 'spin' - which relates to the magnetic properties of charged particles.

The two entangled particles can be in one of two spin states, but cannot both occupy the same state. With regard to the spin state of any single particle we can only talk about the probability that they will be in a given state at any time until we observe it. However, observing the spin of one entangled particle, determines which state the other will be in with 100% certainty without observing it, no matter where it is in the universe. This appears to contradict the limit introduced by Einstein's Special Theory of Relativity (1905) that nothing, not even information, can travel faster than the speed of light. But also, and even more weirdly, before an observation we can only think about spin states in terms of probabilities and the the maths tells us that the combined probabilities of the two particles being in any given state always equals one. The Copenhagen Interpretation says that this effectively means that the two entangled particles are both in both states simultaneously - the two states are superimposed as the jargon goes.

This is quite counter-intuitive, but it has been a boon for science-fiction because the spin states of the entangled particles are linked no matter how far apart they are - "spooky action at a distance" as Einstein facetiously referred to it - which if you aren't too fussy about details gives you an excellent medium for instantaneous communications across the vastness of space.

However, it begs the question: how can something be in two states at once until observed? It was in order to highlight these paradoxical aspects of QM that Schrödinger put his imaginary cat in the imaginary box. With it he placed a mechanism which would release cyanide gas, with a switch triggered by the decay of an atom of Uranium, the timing of which we cannot predict from theory. Close the lid of the box, prime the switch and think: is the cat alive at this moment, or is it dead? If the atom has not decayed the cat will be alive, and if it has decayed the cat will be dead. We can't know until we open the box and observe. Schrödinger invited us to think of the cat as a metaphor for the infinitesimal sub-atomic particle, whose wave was metaphorically entangled with the Uranium atom. If the cat truly was like a sub-atomic particle, then it was both alive and dead until the box was opened, and it was observed to be one or the other. He was trying to show that this is a ridiculous conclusion, and that therefore the Copenhagen Interpretation must be flawed. He lost that particular argument.

A lot of people jump from the picometre scale to the metre scale without any thought for the consequences of a trillion-fold change in scale - even though we know, for example, that our bath water doesn't really behave like an ocean! Or though we know that those pre-CGI movie special effects with models are totally unconvincing. The problem is that in a real cat there are several thousand sextillions of atoms, made up of many particles. Although each infinitesimal particle is a wave and subject to QM effects, these are averaged out over some tens or hundreds of thousands of sextillions of particles. The behaviour of any one particle, or even any million or billion particles, is not going to change the average properties of the cat. Unlike sub-atomic particles, cats simply do not wink in and out of existence; they are not smeared out over space (except perhaps when run over); and we can in fact know quite precisely (compared to the size of the cat) where a cat is and how fast it is moving at the same time. The Uncertainty Principle doesn't apply on the macro level. QM has almost no relevance to the macro world, to a world where objects are made up of septillions of atoms because of the averaging effect of so many particles - if weird stuff was happening we'd never know because a human hair is millions of atoms in diameter. And this is partly why Schrödinger was unable to undermine the Copenhagen Interpretation with this thought experiment, and why it has been co-opted by the targets of his critique, not to mention Buddhists! Actually sub-atomic particles are not alive and it is not ridiculous to argue that they can be in two superimposed states at once, even though it is ridiculous to argue it for a cat. In effect, Schrödinger's Cat proved nothing.

One of the unfinished tasks of modern physics is finding some way to marry QM with Relativity (E=mc² yadda yadda again we don't really understand this). This has proved elusive, though work is going on at both the empirical and the theoretical ends of the problem. So far no one has unequivocal evidence for, say, quantum gravity; and no one has been able to make the maths add up. It may in fact turn out that the two theories are not adequate to the task and that both will be subsumed into some larger construct (some people claim that String Theory will do it, if anyone can ever solve the equations; Stephen Hawking barracks for M-Theory if anyone can both figure out what equations are and how to solve them). Certainly dark matter and dark energy are causing a scramble to rework the Standard Model of Cosmology to account for the observations that gave rise to those terms. Often theories don't survive being scaled up by a dozen orders of magnitude, and this is the case for QM (so far).

It's pretty clear that QM, a mathematical abstraction, doesn't apply to our macro world. However it does have indirect consequences for us as QM issues have to be taken into account in designing new micro-processors which pack millions of transistors into square millimetres; and in nascent nano-technology. But in terms of our daily lives none of the observations of sub-atomic particles apply. None. The similarity of vocabulary is superficial and coincidental, just as the similarity of ethical jargon in various religions is largely superficial and coincidental! well, perhaps not entirely coincidental because like Schopenhauer, both Schrödinger and Niels Bohr were interested in so-called 'Eastern philosophy' and built some of it into the narrative.

Some weeks ago now, in the comments to my post on Rebirth and the Scientific Method Elisa and Krishna were asking: "why do Buddhists feel the need to justify their beliefs by appealing to science?" Part of my answer related to the way the scientific paradigm has dominated our lives for roughly 150 years. Science is incredibly successful in describing the physical world, and predicting new observations and properties of matter. Just look at the recent crop of Nobel Prizes to see the contribution that science makes. In a way it's obvious that we'd want to participate in that. It is a bit ironic that so few Buddhists are educated in the sciences, and tend to approach science with a mixture of abhorrence for perceived materialism, and credulous wonder at its success and authoritativeness.

I don't see much advantage in invoking the talisman of science in defence of religion, especially when on the whole we religieux are so ignorant of science (one of my teachers recently mentioned the way "larger bodies attract smaller ones" in a public talk. He's not an idiot, nor spiritually shallow, but he is clearly, painfully ignorant of science!). It so happens that Buddhists avoid some of the pitfalls of the modern world view (we don't have creation stories for instance), but though monotheism more obviously runs foul of science, I don't think we can sustain our traditional eschatologies, nor claims of ESP powers, nor to know the nature of 'reality', if we are working in a scientific paradigm. It's a minefield.

I don't think Buddhism on its own terms needs any scientific apologetic. Buddhism is originally the product of Iron Age India, and has adapted to many different cultural environments and world-views because, in my opinion, it is not so concerned with the realm of physics, it is concerned with the realm of the mind. Physics provides us with a far superior description of the physical world; but equally in the domain of the mind, and especially the problem of suffering, that Buddhism is far superior descriptively and practically (in terms of practices for working on the mind). This superiority in its own field is not a consequence of levels of technology or an understanding of physics. It's to do with observing our own minds. We don't need a Large Hadron Collider for this. We just need to sit quietly and observe our minds. It is a kind of empiricism, but we don't need to get caught up in making a 'science' out of it.

~~ oOo ~~

Notes

1. This feature of QM not deriving from observations of physical properties was recently the subject of an article in the New Scientist: Webb, Richard. 'Reality Gap' 21 August 2010, p.32-6. NS apparently subscribes to another uncertainty principle as the article title is quite changeable:
   • on the cover - The Ultimate Quantum Paradox
   • contents page - The Ultimate Paradox
   • printed article - Reality Gap
   • online article - Is quantum theory weird enough for the real world? [login required]
   • ScienceDirect article database - Quantum Mechanics: The Reality Gap [login required].
   (return to article)

(Note: Though I gather that Schrödinger loved women and a good party, I confess I'm not really sure whether he owned a cat. Some people claim that Schrödinger was a cat lover, and some that he was a cat hater, but I thought my title was catchy and ran with it. I hope my readers will allow me some poetic licence.)

image: Erwin Schrödinger (internet endemic, i.e. copied so many times that there is no longer a discernible source).

Feynman quotes from Wikiquote.

If you want to learn about Quantum Theory from one of the men who helped to develop it, then I can recommend these three lectures by Hans Bethe: Quantum Physics Made Relatively Simple. As the site says, the Prof is 93 years old and lecturing to the other residents at his retirement home.


Updates to this post

Am I a materialist?

Recently on the Buddhist Geeks website my enthusiastic endorsement of the scientific method was referred to as "dry", "reductionist", and (shock horror) "materialistic". I thought the terms of the discussion were a bit limited. I'm not really much of a philosopher, and have not studied much Western philosophy, but I don't think of myself as a materialist. I understand my philosophical position to be this:

I'm a sceptical epistemological realist; and more vaguely, a transcendental idealist. Though I'm also a pragmatic Popperian empiricist.

The basic position of an epistemological realist is that objects exist independently of your mind. Many Buddhists take the position that objects do not exist independently of your mind, but only exist in conjunction with your mind, or indeed only in your mind. I think this takes the Buddhist argument on the nature of experience too far. I go back to the basic Buddhist teachings and base myself on the idea that consciousness is always specific to the sense associated with it, and arises in dependence on contact between sense equipment, and sense object.

Since all the information we have about objects comes through the senses there are limitations on what we can say about them. But certain consistencies occur. For instance objects are recognisable, and memorable. With reference to any particular object, people agree (more often than not) that there is an object, and also agree on its general characteristics, even though specifics may be disputed. If you could see me writing this you'd probably agree that I'm sitting at a desk, in a room, in a house, in a town, etc; or you'd be open to the charge of madness. If someone else sees an object and communicates to me about it in a way that suggests that they see the same object as I see, then I take that as evidence pointing towards the independence of the object from either of our minds. When everyone laughs at the same time in a movie then it suggests the movie is external to all of us. Explaining observations like these becomes very difficult if objects only exist in our minds.

The view that objects only exist when I observe them at best is egocentric. But consider - when I leave my room and go downstairs to make a cup of coffee, it seems nonsensical to me that my room and all of the hundreds of objects which fill it cease to be because I'm not there to see them. And what about when I blink? In that fraction of a second when I do not see the things, do they disappear? And do they then reappear when my eyes are open again? What happens to them during my blink? Trying to explain this is much more difficult, much more cumbersome, than assuming than that the objects simply exist. However I don't think we can say much about that existence, which is why I am a sceptical empirical realist.

It is my view that the Buddha was unconcerned with the nature of existence, or reality. That is to say he was not concerned with the nature of the objective pole of experience. This lack of concern with existence (and non-existence) is clear in, for instance, the Kaccānagotta Sutta, and strongly re-emphasised in Nāgārjuna's Mūlamadhyamakakārikā. The duality between subject and object is uncontentious in the Pāli Canon, it is simply a given. The conceptualisation of the problem of suffering, all of the analysis, and all of the practices, focus on the subjective side of experience. The nature of the object is simply irrelevant, it has to be there of course, but the arising of suffering is to do with our internal relationship to our perceptions, not with the objects of perception.

I've also said that I'm a transcendental realist, which in a way flows out of the previous paragraph. I must say I'm not a very sophisticated transcendental realist, and not very well versed in Kant or other philosophers of that ilk. Kant began with a problem. Hume had showed that a purely empirical approach to knowledge denied the possibility of metaphysical concepts like causality, time, and space. On the other hand empirical scientists, exemplified by Newton, had shown that we can say very definite things about causality, time, and space. Newton's well-known laws of motion are example. Kant's solution to this was to propose that the human mind interpreted sense experience in terms of inbuilt, or a-priori, categories of knowledge. The very usefulness of Newton's laws showed that a-priori categories had, to some extent, to reflect reality. Kant showed that the subject was involved in the creation of all knowledge, but that knowledge thereby created was valid. We can know useful things about the universe and how it works. Things are more or less as they appear to us.

In terms of my approach to Buddhism what this comes down to is, again, a focus on understanding the subjective side of experience, trying to understand the a-priori, what we bring to our interpretations of experience. This comes out of a study and practice of Buddhism, but in terms of relating it to the categories of Western philosophy this is as close as I've come. The fundamental problem is that we interpret experience in ways that cause us misery. Experience arises out of contact between objects and our sensory apparatus - but it is not the experience per se that is problematic, not the raw experience anyway. It what we make of experience, and how we relate to experience, the stories we tell ourselves about experience that cause us suffering. In other words it is not pleasure per se that is evil, only the pursuit of pleasure with the thought that it will make us happy. Hence the knowledge we need is knowledge of our relationship to experience; knowledge of the way we process experience into views and reactions. It is this kind of knowledge that will be liberating.

The last label I referred to was "pragmatic Popperian empiricist". Karl Popper was to some extent reacting against a trend in European thought which sought to evaluate all knowledge by the criteria of 'verifiability'. That is to say some philosophers were not prepared to accept knowledge as valid unless it could be verified. Sadly, although this philosophical position has long been superseded, it is more or less the popular view that science operates along these lines. But any living scientist will acknowledge the contribution of Karl Popper. At one time it was axiomatic that all Swans were white, because no European had ever seen a Swan that was any other colour. The statement "all swans are white" had become a standard in textbooks of logic even. However when Europeans got to Australia they discovered black swans. One can never anticipate when one might find a black swan which falsifies the statement that all swans are white. And this is the essence of Karl Popper's theory of knowledge, which informs my own understanding, and all of modern science. Facts and laws are only ever provisional because at any time a counter-example may disprove them. Theories might prove to be useful, but they can never be proved once and for all.

I said I'm also a pragmatist and this is because though they cannot be falsified, let alone proved, some forms of knowledge and some forms of practice are useful, or better helpful (I'm not a utilitarian). Some forms of knowledge which have been falsified on one level, even retain their usefulness on another. It is a fact that Newton's Laws remain useful in some contexts - say landing a human on the moon, or designing an aeroplane - even though observations have shown them to be inaccurate, for instance, when considering objects moving close to the speed of light. Then there is the placebo effect, the phenomena that we heal better, if we believe that we have had an effective treatment - even though it may be false to state that we have actually had an effective treatment, still we fair better than if we had no treatment at all. I argued this in the case of karma, which cannot be either verified or disproved, but is still useful as a view in helping to determine how we should behave. That is, I believe the theory of karma is morally helpful, even though it has doubtful truth value, if only in a provisional sense. (see Hierarchies of Values). Despite my definite preference for the rational, factual truth is not the only criteria that I apply when assessing the value of an idea. I may also form an opinion on the basis of helpfulness, or more aesthetic qualities such as elegance or beauty.

I don't feel entirely comfortable with this kind of discussion, or with these kinds of labels, I'm all too aware of the extent of my ignorance of Western philosophy. But when someone calls me a materialist because I'm educated in, and enthusiastic about, the scientific method, I need a way to respond which doesn't buy in to the simplistic duality being proposed: either one is a materialist, or a non-materialist. This simple opposition is not very helpful. People don't really hold views that are either one or the other, but have a far more sophisticated relationship to the objective pole of experience. One simply cannot be a practising Buddhist, as I have been for 16 years, and maintain a purely materialist view of the world. Clearly I do have a view about the material world, and I do think science can tell us far more about the material world than can Buddhism, but my focus is very much on the subjective, on the relationship to perception, on the nature of experience. Traditional Buddhist approaches to knowledge are rooted in pre-technological world-views that are frequently little better than superstition - the Buddha has a magical ability to know ultimate reality through super-powers - which just doesn't chime with my own experience of Buddhists and Buddhism. I see the European Enlightenment as a good thing (unlike some of my colleagues).

The other aspect of the criticism was that scientific investigation is reductionist. Reductionism by definition is the attempt to "explain a complex set of facts, entities, phenomena, or structures by another, simpler set" (the free dictionary). Which means of course that Buddhist doctrine is on the whole reductionist, because at its heart are explanations of phenomena in terms of short lists of mental states and events; and simplified models of dependent arising. By contrast some people try to explain phenomena in terms of more complex, often metaphysical or even mystical, ideas; they go against Occam and invent new entities to explain what they experience. What to call this kind of approach? Inflationist? The inflationist critique of science is that it tries to explain the unknown in terms of the known; whereas inflationists try to explain things in terms of the unknown, and the more mysterious the better. Apparently no one likes to admit that they simply don't know the cause of some experiences, nor the nature of them. If someone claims to remember a past life and I express doubt then I am, apparently, a materialist. But I don't see why an experience should be interpreted in terms of mysterious entities and processes as opposed to known entities and processes, if the truth is that we just don't know.

The charge is that experience is reduced only to that which can be measured. I would turn this around: it seems to me that inflationistists tend to project their subjectivity onto the world, and assign it an objective status which it does not deserve. There are many examples of inflationism stemming from interpretations of Indian religious ideas. Despite all evidence to the contrary people treat cakras, for instance, as really existent rather than symbolic or at best subjective; similarly they insist that the mysterious 'third eye' has some physical manifestation in the body (a past acquaintance assured me that it was connected to the pineal gland!) . I know many people who have seen or felt ghosts, because the house up the road (which is occupied by members of my order and community) is haunted. In fact it is supposedly one of the most haunted houses in the UK. I do not doubt that people have had uncanny, strange, unnerving, and inexplicable experiences. However I also do not necessarily accept that ghosts are the best explanation for those experiences. Some experiences do not have external objects, as anyone who has ever meditated, dreamed, taken psychedelic drugs, or gone mad will confirm. Actually anyone who ever thought, or remembered, or imagined anything is not (necessarily) working with external objects. A ghost certainly has more mystique, than a hallucination, but is it more likely? I'd have to say no. Plus at least half of the weird experiences are obviously caused by sleep paralysis. [See also today's xkcd cartoon]

So, am I a materialist? No. I'm a sceptical epistemological realist, a transcendental idealist, and a pragmatic Popperian empiricist (or something like that - actually I usually just say Buddhist). As such I don't have much to say about the nature of existence or reality (or any of that material stuff). Although I really enjoyed those Brian Cox documentaries and read Stephen Hawking, these days I'm mostly interested in the nature of experience. I do see an empirical approach to investigating it as the most useful; though I'm prepared to be pragmatic about what is helpful for that investigation. The main point is that I reject the dumbing down of religious discussions, especially in the area of the interaction between religion and science. If anything is dry and reductionist, and frankly boring, it is the idea that everyone interested in science is necessarily a materialist.

Next week [22 Oct 2010] I attempt to demolish the idea that Buddhism and Quantum Mechanics have anything in common. See Erwin Schrödinger Didn't Have a Cat.

Rebirth Eschatologies

The word eschatology derives from the Greek eschato 'last' and refers to belief systems related to the destiny of individuals and groups, especially after death. Last week [see Brahmā the Cheat] I drew attention to Gananath Obeyesekere's fascinating book on rebirth eschatologies - Imagining Karma - published by the University of California Press (2002). This week I want to look more closely at his ideas. By comparing various belief systems around the world Obeyesekere teases out the essential features of belief in rebirth, and then looks at Buddhist, Amerindian, and Greek belief systems in light of these generalities.

The simplest form of rebirth is a usually unending cycling between this world and another world. Richard Gombrich (who has collaborated with Obeyesekere in the past) has highlighted the work of Polish Sanskritist Joanna Jurewicz which shows that contrary to prevailing views there is evidence of just such a belief system in the Ṛgveda: the brahmin goes to the world of the fathers for a period after death and then returns to this world. Jurewicz identifies a single verse in a late hymn which appears to confirm a belief in this kind of rebirth. The late timing suggests that the idea comes not from the group who wrote the Ṛgveda, but rather than the they picked it up after they had been in India for some centuries. [1]

The simplest form of rebirth eschatology is not moral, rebirth is not dependent on behaviour and so the other world is not differentiated, and this kind of rebirth is the commonest around the world. As soon as morality is introduced into the picture the other world bifurcates into a place of reward, and a place of punishment. In this model good deeds cause one to be reborn in heaven for a period until the merit of the previous life is exhausted, when one returns to this world. This morality need not be ethical. For instance in the morality of brahmins one's destination after death was dependent on proper ritual behaviour, not on ethical behaviour. Just as for centuries Hindu morality focussed on doing one's duty, rather than on one's behaviour more generally (a central theme in the Bhagavadgīta).

A further development occurs when the rebirth destination in this world (as opposed to the other world) is determined by morality in the previous life. This is roughly the situation of the rebirth theories in the early Upaniṣads: Bṛhadāranyka (BU), Chāndogya (CU), and the Kausitaki (KauU). [2] The 'doctrine of the fires' maps out a relatively complex set of possibilities. On death the one who has understood the identity of ātman and brahman goes to the gods and then onto brahman and does not return [3]. The one who has carried out the sacrifices (i.e. a brahmin who follows the pre-Upaniṣadic religion) goes to the world of the fathers and is eventually reborn as a human (which is the old simple cycle). The third possibility is for everyone else and they are reborn as a śudra or an insect - they don't have an account for the other classes, or any women.

The ethicization of rebirth changes the model substantially into what Obeyesekere calls a karma eschatology - something which appears to be unique to India. This is where one's ethical actions (karma) determine one's next rebirth (though confusingly karma meant ritual action to the brahmins). Although there are hints at an ethical rebirth in BU, the idea is first found fully articulated amongst the śramaṇa groups. Some scholars have taken this to mean that the idea originated amongst śramaṇas and was only later adopted by brahmins, and argue that BU especially shows this absorption in process of happening since it presents different patterns of rebirth. The fact that the ideas about rebirth are presented by kṣatriyas in BU and CU helps to reinforce this interpretation.

In earlier models rebirth was an endless cycle, which came to be called saṃsāra - meaning 'continues to go on'. This idea must have persisted into the Buddhists period even though middle Vedic period texts like the Śatapatha Brāhmaṇa (ca 8th-6th century BCE) mention the possibility of escape from the cycle of 'redeath' as it is called there. We know this because many of the Buddha's teachings are given in terms of an escape from saṃsāra, where saṃsāra is precisely this beginningless, endless cycle of birth and death. Buddhists were not the only group teaching an escape from saṃsāra, and this seems to have been one of the most important religious paradigms both at the time, and subsequently. In the early Upaniṣads, as I have mentioned, escape from the cycle was conceived of in terms of 'going to brahman', or 'union with brahman': brahmasahavyata. I have discussed one of the Buddhist responses to this belief in the Kevaddha Sutta in an earlier post. Here we find the Buddha claiming:

I know Brahmā, and Brahmā's domain, and the way leading to Brahmā's domain.

The result was not to deny the escape from saṃsāra in terms of the path to brahman, but to adopt and adapt it. At present I do not think the very distinctive nature of the brahmavihāra meditations with respect to other styles of Buddhist meditation has received sufficient attention. This may be because later Buddhists lost sense of the metaphor and read brahmavihāra as literally being reborn in Brahmā's world, i.e. as not leading to freedom from liberation, despite the related description cettovimutti being applied to it. My reading of the texts, following Gombrich, is that the Buddha clearly used brahmavihāra as a synonym for nibbāṇa.

So the Buddhist idea of an escape from saṃsāra was not original. What was original was how the Buddha defined 'this world' and what escaping from it meant. I have explored the former in my post What the Buddha meant by World, and clearly his definition of 'the world' as the world of experience, has profound implications for eschatology. What we are escaping from is not necessarily birth and death in the sense of physical rebirth, and physical death. Indeed the Buddha often couched his eschatological teaching in terms of escape from the experience of disappointment (dukkha). It allowed the Buddha and other arahants to say they were liberated, that they had "done what needed to be done" in their own lifetimes, without the necessity to die first (an innovation on the Brahmin conception at least!). Heaven, dwelling with Brahmā (brahmavihāra), is available here and now, according to the Buddha.

Historically Buddhists seem to have taken on existing cosmologies with some adaptation, but with a tendency to reify them for rhetorical effect. Although the Buddha defined 'this world' in terms of experience, the 'other world' became a series of actual places where one could be reborn: the brahmaloka in particular was brought within saṃsāra. This seems to have been a wrong turn, and has left us with a confused picture of cosmology and rebirth. Tradition asks us to believe quite literally in rebirth and in the various realms. The spirit in which the Buddha claimed to know Brahmā and the way to companionship with Brahmā - as a metaphor for escaping saṃsāra - has been lost. One result has been the ongoing polarisation about whether or not we Western Buddhists should believe in rebirth. On the contrary Chögyam Trungpa has spoken of the six realms as psychological metaphors rather like the Jungian archetypes, and this sits better with the idea of 'world' as experience, than more traditional realms for actual rebirth. [4]

One of the weird things about rebirth and karma eschatologies has been the enthusiasm for them in the West. For the Indian repeated rebirth and redeath is a curse to be escaped from. In the popular imagination of Western culture, rebirth seems an attractive proposition. We actually want to be reborn. What this tells us is that westerners in general see rebirth in terms of personal continuity. This is what the Pāli texts call 'having a pernicious view' (pāpakaṃ diṭṭḥigataṃ). When nibbāṇa is presented in terms of the end of personal continuity, I think something baulks in the Western psyche. It suggests that despite living in hedonistic and nihilistic times, that underlying this is a frustrated eternalism. Having given up on the prospect of eternal life somewhat reluctantly because of the accompanying baggage, we are drowning our sorrows. Perhaps this is also why western culture is so obsessed with youth, so mired in the Peter Pan Syndrome.

It is unlikely that Obeyesekere's book will appeal to the mass market, or even to most Buddhists. The ideas are complex, even if well presented. Complex ideas are difficult to popularise, especially in our 'sound bite' culture. However the more that we understand about how the early Buddhist presentation of the Dharma was conditioned by the time and place of its articulation, the better we will understand how to adapt it to our own times. The aspects of the Dharma that are simply cultural will stand out better, allowing us to grasp more clearly the principles which are applicable in our own context.


Notes

1. Jurewicz's original paper was: Jurewicz, J. ‘Prajapati, the Fire and the pañcagnividya’. In: Balcerowicz, P., Mejor, M. (Eds.) Essays in Indian Philosophy, Religion and Literature. Delhi: Motilal Banarsidass 2004, s.45-60. A revised version of her conference paper from the 14th World Sanskrit Conference, July 2006, on this subject is on the Oxford Centre for Buddhist Studies website: Jurewicz, J. The Rigveda, 'small scale' societies and rebirth eschatology. 2006.
2. KauU contains a later reworking of ideas found in BU and CU.
3. I have pointed out that this idea is missing from the Pāli texts. The omission is significant, but so far not much commented upon in the academic literature. One scholar who has also noticed this is Dr Brian Black of Lancaster University, watch for a series of forthcoming publications from him.
   
4. See Trungpa's commentary in Trungpa, Chogyam and Freemantle, Francesca (trans.). The Tibetan Book of the Dead: Great Liberation Through Hearing in the Bardo. Shambala, 1975. (link is to the new edition)
   

image: Monks stand waiting for a confession as a martyr is tortured on the wheel. Taken from How Stuff Works, ultimately from Hulton Archive/Getty Images.

Brahmā the Cheat

The Brahmanimantanika Sutta (MN 49) has a number of interesting features. The sutta opens with the news that Baka the Brahmā has taken on a wrong view. Baka means 'crane' or 'heron', but it has figurative meaning which is according to Monier-Williams: "hypocrite, cheat, rogue, the crane being regarded as a bird of great cunning and deceit as well as circumspection)". We should immediately be alert therefore that this is a polemic. The animal with the same characteristics in Anglo-European culture is the weasel - so the character's name might be rendered God the Weasel.

The view that Baka has taken up is this:

Idañhi, mārisa, niccaṃ, idaṃ dhuvaṃ, idaṃ sassataṃ, idaṃ kevalaṃ, idaṃ acavanadhammaṃ, idañhi na jāyati na jīyati na mīyati na cavati na upapajjatī’ti; santañca panaññaṃ uttari nissaraṇaṃ ‘natthaññaṃ uttari nissaraṇa’nti vakkhatīti.

This, sir, is permanent, this is enduring, this is eternal, this is everything, this is unending. This is not being born, is not aging, is not dying, is not falling, is not being reborn; and beyond this, there is no escaping.

Our first question is what does Baka mean by 'this', what is he referring to? And because the text moves swiftly on to another tack it is difficult to tell. However there is a clue in the passage I've cited, in the sequence: birth, aging, death, falling, rebirth. This is not a random sequence, nor are death (mīyati) and falling (cavati) simply synonyms as one might easily assume them to be, nor perhaps are birth (jāyati) and rebirth (upapajati).

I need to backtrack for a bit. In 2002 Gananath Obeyesekere published Imagining Karma: Ethical Transformation in Amerindian, Buddhist and Greek Rebirth, which took a broad view of the idea of rebirth. It seems that many cultures develop a theory of rebirth and in its most basic form it involves circulating between this world and another world - usually some form of heaven, often inhabited by one's own ancestors. It has been asserted for a long time that in the early Vedic period there is no evidence of a belief in rebirth, but more recently Joanna Jurewicz showed that the Ṛgvedic mantra 10.16.5 can be interpreted as a request for Agni to send the dead person back again to his descendants (this is discussed in Richard Gombrich's 2010 book What the Buddha Thought). This suggests that early Vedic people had a standard rebirth theory in which the person (actually the man) cycled between this world and the other world.

The 'other world' for the Vedic Brahmin was the world of the fathers (pitaraḥ). This idea is expressed in greater detail in the Bṛhadāranyaka and Chāndogya Upaniṣads which both tell the story of how one precesses through the cycles. However the simple binary persisted for some time and it is referred to in the Pāli texts (in the phrase 'this world and the next world'). The simplest expression of this cycle does not allow for escape.

Let us now reconsider the Brahmanimantanika Sutta. The sequence, again, is: birth, aging, death, falling, rebirth. The cycle involves being born (jāyati) and living in this world (jīyati); dying (mīyati) and arising (upapajti) in the heavenly realms. Having lived a long time in the heavenly realms, one falls (cavati) back down to earth to be once again born (jāyati). And so the cycle goes round.

This cycle is called saṃsāra which is a noun from the the verb sam+√sṛ 'flow' - and means to move about continuously, to come again and again. It is this that Baka is saying is "permanent, enduring, eternal, everything, unending". This is his deceit: the view he adopts is that saṃsāra is forever, and inescapable, that we are doomed to go around and around endlessly. The ethicization of the universe that occurred amongst the samaṇa movements meant that the model had to become more sophisticated, but I will leave that thread for now. But the idea that one could escape from the rounds of rebirth (or redeath as it is sometimes called) must have seemed extremely radical. Indeed the Upaniṣads the idea is introduced to Brahmins by a King or Kṣatriya, and although there is much speculation about what this might mean, at the very least it shows that the idea was new and from outside fold.

Māra steps into the sutta at this point and his contribution at first sight is puzzling. However Māra is sometimes called Namuci, which is a contraction of na muñcati 'does not release'. His role often relates to keeping beings in saṃsāra. Māra as an archetypal figure is often associated with our own doubts, he is the inner voice of doubt. So whereas Baka seems to represent the social pressure exerted on us to doubt the possibility of liberation; Māra represents our own doubts.

One of his warnings to Buddha is:

so... mā tvaṃ brahmano vacanaṃ upātivattittho... evaṃ sampadamidam bhikkhu, tuyham bhavissati
He... do not overstep what Brahmā says... [or various evils] will befall you.

This is reminiscent of the debate scene in BU 3.6 where Gārgī is questioning Yajñavalkya on what the various aspects of the universe are made; and finally asks on what brahman is woven. Yajñavalkya replies

sa hovāca gargī mātiprākṣīḥ
mā te mūrdhā vyapaptat

Don't ask too many questions, Gārgī
your head will split apart.

Gārgī desists, but later in the text another questioner's head does split apart.

Of course Māra also plays the role of Lord of saṃsāra - he thinks of the kāmaloka as his realm, where we dwell at his mercy, which is to say we dwell suffering. Māra is afraid that if the Buddha teaches that beings will go beyond his realm (te me visayaṃ upātivattissanti).

Then the Buddha and Baka have a discussion about the elements. Baka says

Sace kho tvaṃ, bhikkhu, pathaviṃ ajjhosissasi, opasāyiko me bhavissasi vatthusāyiko, yathākāmakaraṇīyo bāhiteyyo

If indeed you, bhikkhu, will be attached to earth, you will be in my domain, in my reach, at my mercy.

This is repeated for a list of elements. Of course the Buddha is aware of this and says that he not attached to the elements. The list of elements is unusual: earth, water, fire, air, beings (bhūta), devas, Prajāpati and Brahmā. Once again I refer the reader to BU 3.6 and the discussion with Gārgī. It goes like this (I'll use Valerie Roebuck's translation, slightly modified)

"Yajñāvalkya, she said, since all this earth (idaṃ sarvaṃ pārthivaṃ) is woven on the waters, as warp and weft, on what are the waters woven?
On air.
On what is air woven?"

And so on. The list begins the same: earth, water, air. Then we get 'the middle realm' (antarikṣaloka) which may well correspond to bhūta in the Pāli list. Then in BU a list of various devalokas - gandharvaloka, adityaloka, candraloka, nakṣatraloka, devaloka, indraloka - then prajāpatiloka and finally brahmaloka. If we collapse the list from gandharva to indraloka into 'devaloka' (which they are all varieties of) then the list from Brahmanimantanika Sutta and BU are very similar indeed. What's more the list makes more sense in the context of BU than it does in a Pāli sutta, because the Buddha was hardly likely to be attached to Prajāpati or Brahmā.

There is one snafu here. And it is that one of the distinctive teachings of the BU, which we meet at the end of book 3 (3.9.28), is the idea of escape from rebirth:

jāta eva na jāyate ko nv enaṃ janayet punaḥ |
vijñānam ānandaṃ brahma rātir dātuḥ parāyaṇaṃ ||

Born, only, not born again; who could beget him?
Consciousness, bliss, Brahman, grace; the gift to the giver.

It seems that in all of these kinds of references to Vedic ideas in Pāli texts, there is always an element of over-simplification, of parody. One gets the sense that the last thing a Buddhist wanted to do was debate a Brahmin on their own terms - and yet again so many of the converts seem to have been, at least nominally Brahmin.

In Brahmanimantanika Sutta we seem to have some quite clear references to Upaniṣadic ideas. However as I noted in Early Buddhists and Ātman/Brahman the references are to cosmology rather than to the more central details of the Upaniṣadic thought. It seems as though the cosmologically notions had been popularised, or perhaps more likely that the cosmology recorded in the Upaniṣads represents a popular tradition rather than a specifically Upaniṣadic tradition - I would make the contrast with the identification of ātman and brahman, which is not found in the Pāli texts.

Rebirth and the Scientific Method

I've been involved in a desultory discussion via comments on the blog Buddhist Geeks on the subject of reincarnation and the scientific method. This was sparked by a blog post entitled An Evidence Based Spirituality for the 21st century. In it Charles Tart argues for a scientific approach to ESP and reincarnation (Tart seems to prefer this term to 'rebirth') based on what he considers to be "solid evidence". I have a life-long interest in science, and studied it at school and university. Having invoked the scientific paradigm I think that Mr Tart needs to follow through on the implications of it, and here I will explore some of the them. I want to look particularly at reincarnation from two different points of view - methodological and philosophical - and show that we are far from having a scientific account of reincarnation.

The Problem of Method.

Mr Tart cites some 4000 cases collected at the University of Virginia Medical School, where research and publication continues on this subject, especially by Dr Jim Tucker. Tucker's informants, as Tart says, are children between the ages of 3 and 6; and the 'evidence' is the testimony of these infants. So already we must register some concerns. The theory of mind, the ability to distinguish others as self-conscious individual beings, only develops at around 3 or 4 years. Very young children like this have some difficulty distinguishing self from other; truth from fantasy; memory from imagination; overheard conversation from their own thoughts. So we must doubt their reliability as witnesses. As in legal cases, how one questions very young children has a strong determining effect on the answers you get. We could not accept this kind of 'evidence' without detailed scrutiny of the method - something which would be time consuming and beyond the scope of a blog post. For instance one group of researchers looking at children's evidence in sexual abuse cases conclude:

"It is now acknowledged that persistent suggestive questioning can lead children to provide accounts of events that never occurred, even when they first denied them. Sometimes the questioning results in the child developing a subjectively real memory for an event that never happened."

Such conclusions are widely replicated across a number of different disciplines over the last couple of decades. Even in adults memories are very plastic and subject to change; and subject to invention; imagination can come to seem like memory. Stories repeated by family members can come to seem like personal recollections, even when we weren't there, or born yet. Often the way we recall a situation depends on the emotions associated with the memory. This is why anecdote is seldom invoked as evidence by scientists. The fact that most of the informants are under six may well mean that after that age the distinction between fantasy and fact becomes clearer, or that the children are less able to be lead by enthusiastic researchers with something to prove.

The claim is often that the person could not possibly have known the details of their account from personal experience in this life. Having just trashed anecdote, I'll risk hypocrisy by sharing something from my own life. For years I had memories from childhood which involved an unaccountable knowledge of and respect for Buddhist monks. As a child I understood what meditation was, and once or twice sat down to meditate. It has a lot to do with why I was attracted to Buddhism as an adult. I grew up in a small town in New Zealand and I could not possibly have had contact with Buddhism in my childhood, as far as I know there were no Buddhists within a hundred miles. There was no way for me to have such knowledge from this life. Or so I thought. Last year I started re-watching the old TV show Kung Fu, and realised that this was the source of my 'memories' - it all came flooding back. I'd loved the show as a kid, 30+ years previously, but had simply not made the connection partly because so many years had passed.

If someone, especially a young child, says that they remember a past life, or even if they only appear to have a memory which cannot be explained, that is not the same thing as them actually having had a past life. How would one establish beyond any doubt that a so-called memory was of a past-life? We can easily accept the idea that people have a memory that they cannot account for; but why assume a past-life is the best explanation for this?

I propose this test: one of these people who recalls a past life could predict some previously unknown historical fact, that could then be shown to be true by previously unknown archaeological finds. Get the subject to make a prediction, publish it well in advance of the search, and then go off and dig and find some previously unheard of city or civilisation which substantially confirms the predictions of the person. A variation on this procedure might including getting the person to predict the discovery of the previously unknown species recorded in the fossil record, and then discover a fossil just as described. Or they might show how to read a previously undeciphered script. Something that only a person living in that time and place could know, and that is entirely unknown to us now.

The value of a scientific theory is in the predictions it makes. I would be very interested to hear about any peer-reviewed publication in which a past-life recollection told us something new about the world in the way that I've outlined.

[7 May 2014 - a thorough assessment of the methods and conclusions of another reincarnation enthusiast, Dr Ian Stevenson can be found at the Skeptics Dictionary.]

Philosophical Problems.

The basic contention of Tart et al is that empirical methods can be used to demonstrate metaphysical ideas or perhaps we should say 'abilities' such as extra-sensory perception or recollection of past lives. They are saying that such ideas are demonstrable and measurable, and therefore not really metaphysical, i.e. not beyond physics. However there is a kind of placebo effect at work: ESP is only detectable if you believe in it in the first place. Presumably this is what has gone wrong in all of the properly controlled studies which have shown absolutely no evidence in support of ESP and the like. On the other hand there is also the fact that a desire to believe has allowed charlatans to pull the wool over the eyes of the credulous in a number of cases. The best known, and funniest, of which is the Project Alpha, a hoax perpetrated by some (sleight of hand) magicians which exposed the credulity, and poor methods, of ESP researchers.

When, in 1915, Einstein proposed that gravity is better understood as the bending of space by masses, it might just have remained another novel idea if Arthur Eddington had not demonstrated in 1919 that it is indeed the case. Eddington's observations of the transit of Venus demonstrated that masses bend light, which itself has no mass, as it passes close by them. In the face of this kind of evidence, the world then accepts this new idea even though it is counter to the prevailing view and even counter-intuitive (how can something with no mass be affected by gravity?). The same thing happened with Quantum Mechanics which was not accepted without some fierce opposition lead by none other than Albert Einstein, and now underpins the technological revolution. The same thing is currently happening in cosmology as empirical evidence accumulates that the universe must contain more mass than we can see or our theories predict (dark matter), and that something is pushing galaxies away from each other (dark energy).

Sometimes paradigm changes can be theory led, sometimes observation led. However the empirical side of things is based on published observations which are then repeated by an independent third parties, who often have a vested interest in proving their rivals wrong! It is the build up of repeatable results that creates the pressure to change a world view - and let's be clear that our views of the world can and do change from time to time. The dark matter/energy observations will eventually change our understanding of the cosmos for instance. So called 'cold fusion' by contrast could not recreated in any of the labs which tried, and it soon became apparent that the announcement had been premature to say the least. ESP has being researched for 200 years without coming up with one uncontestable result, while at the same time many frauds have been exposed.

Reincarnation fans complain that if scientists would only apply empirical methods to the study of reincarnation they would see it is real. But equally if a scientist reports a negative result it is because they are too materialistic, and not open to new ideas (tell that to any astronomer or nuclear physicist of the last century and they might beg to differ). Usually an unequivocal negative result requires a scientist to abandon their theory (e.g. phlogiston, or the æther) and seek a new explanation.

There is a much greater philosophical problem with so-called memories of past-lives, and it is one that plagues all theories of rebirth/reincarnation. Such theories suggests a continuity between lives, over multiple lives, a personal continuity. This raises the question about the nature of that continuity? There must be some aspect of our being, not reliant on our physical body, which goes from life to life, collecting and preserving memories, and then later allowing our present consciousness reliable access to those memories, though apparently only during childhood. What can survive intact through multiple lives and deaths, and accurately preserve memories? I know of nothing which would meet the requirement except a soul of some kind.

Now, if science is to offer any insight into the phenomena at all, then it would be in establishing the existence of, and the mode of functioning of this soul-like phenomena which provides a medium for memory storage external to the body, and particularly the brain. They would show how and where such memories are stored. Of course they must take into account the well demonstrated role of the brain in the formation, storage and recall of memories of living humans - we can lose all of our memories and the ability to make new ones through brain injury. (I recommend Joseph LeDoux's book The Emotional Brain for a survey of the history of this field). The idea that memories survive the death of the entire brain, and surface sometime later in a person with no close genetic relationship, requires explanation. Tart et al, having invoked the scientific paradigm, must seek to explain it within that paradigm. It's up to people like Mr Tart and his colleagues and supporters to come up with the theories that can be tested, with measurements that can be made. As I understand it they do not propose mechanisms for metaphysical memories. They do not propose theories that can be tested. They merely churn out anecdote. It is not sufficient for the idea to be taken seriously to invoke the "50 million Elvis fans can't be wrong" argument.

In Conclusion

I think it is only right to be sceptical towards the idea of recollection of past lives. It is a deeply problematic metaphysical belief. It will not be easy to demonstrate that life continues after the death of the individual, and as far as I know this has yet to happen. My view is that a belief in past-life recollection is more than likely linked to a deep desire for personal continuity. It's poignant, it's understandable, but it is entirely unscientific. By invoking science the meta-physicians are caught out. If the phenomena is material enough to be observed then it must either obey known laws, or we must recast those laws to account for it. But if it really is as described in faith texts, then it is not dependent on the material world and will be forever beyond the reach of empirical science. So why invoke the scientific method in the first place? I will have to leave this question hanging, but it is one I must come back to. The conflict between the ancient world views preserved in the amber of religious faith, and the modern empirical world view is on-going.

Update: 10.10.2010

Anyone interested in the way memory works will be fascinated by this story from the Guardian Newspaper: Meredith Maran: Did my father really abuse me? It is an extract from her book My Lie: A True Story of False Memory, which looks at the way one intelligent and articulate woman manufactured 'memories' of incest out of a febrile imagination, on the basis of her deep (and positive) involvement in the issue of sexual abuse, and a culture which demonised men. I don't think this in any way trivialises the issue of sexual abuse, but it does give us insights into the complexity of the mind, and memory in particular.

Thanks to my friend Vidyavajra for bringing this to my attention.

Update 24-7-11

This cartoon on Calamities of Nature is apposite. As it says: either souls interact with the world and are within the province of science; or they do not, in which case why should they concern us?

Update 7 May 2014

Sean Carroll a real scientist talks about life after death: Physics and the Immortality of the Soul;