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The Very Real Ghost of a Demon

by Paul Tappenden

As a child, I was intrigued by thoughts of a randomized TV. The idea was simply that the screen should be connected to some sort of random signal generating device which could throw up any possible picture and would produce permutations at the rate of, say, one per second. I thrilled at the notional power of having access to views of any planet in the universe, real or imaginary; views from any possible angle a TV camera could record. The magical device would show portraits of every possible person, human or alien, and extracts of text from every possible book. It would also show every possible finite sequence of pictures; past and future events would unfold just as they had done and would do and in every way they might have done and could do.

A TV screen is an array of luminous cells (pixels) of different colours which can vary stepwise in brightness and each picture is describable as an ordered set of cell brightnesses. That is, to describe a picture you could start at the top left corner of the screen, give the colour and brightness of that pixel, then the next to the right and so on until you had systematically zig-zagged down to the bottom right corner. For any screen there is a finite, though unimaginably huge number of possible pictures it can show and each of those pictures can be thought of as a particular screen-state; each sequence of pictures a series of screenstates.

I was aware, insofar as anyone can be, of the impossible tracts of time the machine would need to reveal its wonders and, in retrospect, the fantasy demonstrated the immensity of some easily written numbers as much as anything else. For if you could watch that randomized TV continuously for as long as the Earth has existed, 5 billion years, it is extremely unlikely you would ever see anything but a grey haze on the screen.

Some Devilish Physics

Some physicists believe, and none has yet effectively been able to deny, that quantum mechanics (QM) is not only relevant to the realm of the microscopic but applies to larger objects too. And if QM is widely applicable in this sense then ordinary material objects such as a human body are a bit like series of TV pictures. At any moment, your body is in a physical state and over a period of time it conforms to a series of states rather like a series of pictures on the screen. The series of body-states may be continuous whereas the series of screen-states is discrete, but the point to be made is that just as it is possible for two TV screens to be in the same series of screenstates, to show the same run of pictures, so it is possible for two physical objects such as human bodies, according to QM, to be in the same series of physical states for any duration.

There is another partial analogy between picture series and the body. The imagined screen showed its pictures independently of what was going on in the world around it. QM does not say that a body-state is independent of its surrounding world but it does say that the dependence is probabilistic. Of course, physical objects are mutually interactive in many ways. We’ve heard the stories about how what happens in another galaxy can affect our weather. But QM tells us that no event has a uniquely predetermined effect, though the probabilities of possible outcomes can in some cases be calculated very accurately. It is accuracy in calculating probabilities which gives QM its enormous power.

You may have heard how at any time all the air in a room could collapse into a corner, leaving the rest of the room evacuated and imploding under the enormous external atmospheric pressure. According to QM that is perfectly possible, though desperately improbable. Another possible improbability is that a telephone could materialise on a table and promptly turn into a bowl of cherries. Such behaviour would not violate any laws because, according to QM, the rest of the world would have changed in one of many sorts of suitably compensatory ways. And this is not a wantonly perverse interpretation of QM. Given world enough and time it is very unlikely that such bizarre events would not happen. You would have to wait vastly longer than the currently supposed age of the universe to see a telephone spontaneously turn into a bowl of cherries, but if you could watch long enough it would be virtually certain to happen.

Being in a State

Now, there’s a widespread view of the world and our place in it which sees the state of a person’s consciousness at any time as entirely due to the physical state of their body or some part of it, particularly the brain. We could call this common materialism (CM). It is a view which has created a lot of philosophical heat for a long time, and still does so. What I want to demonstrate is that, in the light of our best understanding to date of the material universe, CM leads to a strange consequence for our idea of what ordinary material objects are. Far from thereby undermining CM, I want to argue that this strange consequence could be very enlightening in our struggle to come to grips with the strangeness of modern physics.

Rather than quibbling over which part of our bodies, according to CM, is the seat of consciousness, let’s just suppose that it is the whole body; all that follows will apply just as well to any preferred part. Of course, one’s consciousness at any time can seem to include memories and thoughts about distant objects. But according to CM this can all be accounted for by what is the state of the body at the time. We remember because of some sorts of recordings within our bodies, we think about the world because of some sorts of representations of the world within our bodies, representations which can be more or less true to the way the world actually is and which can serve as a base for constructing fantasy worlds of possibility and even impossibility.

You are conscious now of reading this magazine, unless it’s being read to you, and of various other things too, no doubt. According to CM this is all due to the state of your body and the state of your body is not accidental. Because there is print in front of you reflecting light to your eyes in particular ways and because your body is equipped with a certain interpretative apparatus, there is something going on in you which is the seat of your seeing print and which is a direct result of the relevant print being in front of you. That is, your body-state and the world-state are in some sort of correspondence.

But, according to QM, your body could be in the very same state and yet the world be in quite a different state. Things could be so different in fact that your body could be in just the same state yet be floating in deep space. This is a very bizarre situation indeed, and QM would calculate the probability of such a situation being sustained for any length of time as unimaginably minute. Normally, your lungs would collapse and you would perish very quickly in great distress. But we are imagining an abnormal situation: improbable events happen to keep an envoided body just like yours intact and in a series of states just like those your body is in now. The point is that this situation, however improbable, is possible according to QM. There is an amusing little story by Bertrand Russell entitled The Metaphysician’s Nightmare which makes use of bizarre improbabilities of this sort [1] .

The question now is how, according to CM, you can possibly tell that you are not in fact floating in void rather than reading this magazine. Everything would seem just the same. Whatever you tried to do to establish the reality of the world as you take it to be could only enter your consciousness via the physical state of your body and that could also have arisen in the void. Of course, if you believe in CM and QM you will regard the possibility of your floating in void as absurdly improbable and so not worthy of any serious consideration; but it is possible. Everything could seem to you just exactly as it does now yet your consciousness could be that of an envoided body.

We have arrived at the concept of total hallucination. The 17th. century philosopher René Descartes arrived at the same concept by a different route, an event which is often taken to mark a turning point for philosophy into the modern age and which was a reemergence of an ancient Greek scepticism. Here is a translation of how Descartes put it in his Meditations, first published in 1641:

“I will suppose, then, not that Deity, who is sovereignly good and the fountain of truth, but that some malignant demon, who is at once exceedingly potent and deceitful, has employed all his artifices to deceive me; I will suppose that the sky, the air, the earth, colours, figures, sounds and all external things, are nothing better than the illusions of dreams, by means of which this being has laid snares for my credulity;” [2].

A clear difference between Cartesian scepticism and the view based on QM + CM which I am proposing is that Descartes used ordinary intuitions arising from our experience of dreams and delusion whereas I am invoking a sophisticated theory about the nature of our bodies as material objects, in conjunction with CM. Descartes’ ‘argument from error’ has been criticised on the point that the very idea of error presupposes a context of veridicality. On this criticism, the concept of total error, total hallucination, is incoherent because it ignores the very presupposition of veridicality which is necessary to the concept of error.

In a similar vein, it could be argued that if you had an envoided body you would have no grounds for believing in QM at all so the very idea that you could have an envoided body would have no justification if you were indeed envoided. However, I can allow that it is incoherent for you to believe that you are envoided whilst at the same time insisting that it might actually be the case that you are. Within the consciousness of both a normal and an envoided body a world could be seemingly seen, but an envoided subject could not actually see anything. And there is scope for similarly arguing that an envoided subject could not actually believe anything either, or at least that its capability to believe would be severely curtailed. Another way of putting this is that we are never conscious of seeing or believing but only of seemingly seeing or seemingly believing. There isn’t the space here to argue this point in detail but I hope that I have at least been able to indicate that the difference between the structure of my argument and Descartes’ argument from error means that the problem of Cartesian scepticism need not necessarily arise.

Descartes saw his task as to reason his way out of a compartment of a philosophers’ hell; to salvage something solid beyond the demon’s reach and build a reality from it. I am not concerned here with that enterprise. What I want to do is to show that the concept of total hallucination, when juxtaposed with our everyday view of the world, leads to an important insight into the fundamental nature of material reality. It is not a new insight, the idea is one which has haunted philosophy for millennia but for all sorts of reasons it has been denied or not acknowledged with naked clarity. And not since the advent of QM, in the 1920s, has fundamental physics seemed so puzzling as to challenge our deepest preconceptions about material objects in a way which makes that old philosophical idea seem especially pertinent.

Phenomena and Noumena

Once the possibility of total hallucination has been accepted it is a short step to the conclusion I wish to draw. Take any ordinary situation where you identify a physical object. You look at it, perhaps, feel it, test and measure it in various ways to establish that it really is what it appears to be. And you take into account the reports of other observers and compare them with your own seeming perceptions. This whole experience of verification cannot be conclusive, though it is the best you can ever hope to do in establishing the nature of a physical thing. But that whole experience of verification could also have been an hallucination. The difference between the object really being there and not being there at all is not anything which enters your consciousness because your consciousness is exactly the same in both cases.

It follows that there is no reason to suppose that whatever it is which materially exists has any physical properties at all. Because physical properties are properties which things only appear to have, however prolonged and involved the process of testing and measurement. And it is not these appearances which make the difference as to whether a thing really exists or not. However improbable you may think it is that you are envoided, the mere possibility that that may be so is enough to demonstrate the radical ‘invisibility’ of the things we ordinarily take to exist.

I am not claiming that this magazine does not have physical properties, only that it need not have. What it must have, if it is here, is properties which make it appear to have physical properties. And, again, I do not mean just immediate superficial appearance, but its appearance under any tests you try to perform on it. There is no reason to suppose that this magazine has mass, electric charge or any other physical property, including spatial extension and duration.

The idea can seem very strange, and I must reiterate that it is not to suppose that the magazine, if it exists, has no definite properties. If it exists, it must be something quite special in order to appear as it does and not as a banana. And any physical object must be something quite special in order to appear to us, according to systematic tests and measurements, with all the complexity of physical characteristics which physics describes.

You might query that to appear to us as anything at all an object surely must be able to affect us in some way, to register itself on our measuring instruments and on our sense organs, and how can it do that without physical properties? And it is true that it must be able to affect us, but note that the argument applies as effectively to our bodies as it does to the magazine. We also need not presume that our bodies have physical properties and so need not require physical properties of things affecting our bodies. Again, that is far from saying our bodies are nothings. They are things so special as to be conscious.

The argument leads to a fundamental dichotomy between things as they are for-us and things as they are in-themselves. It is a dichotomy which was at the heart of Immanuel Kant’s philosophy, though it had a different character for him in important ways and he arrived at the conception differently. Kant divided the world into the realm of phenomena, the publicly determinable appearances of things, and noumena; things in-themselves. To Kant, there was something deeply inscrutable about noumena, but for us, with the benefit of two further centuries of philosophy, science and mathematics, a reconstrued form of noumena may in at least some respects be more accessible.

The theoretical physicist Bernard d’Espagnat has recently stressed the importance of something like the Kantian dichotomy:

“Unless we discard altogether the very idea of a reality that is independent of our knowledge, we have to accept that such a reality cannot be identified with the ensemble of phenomena. This in turn means that we cannot escape what I claim is the fundamental distinction between reality in itself or as such – reality independent of human minds – and the ensemble of phenomena – or empirical reality.” (d’Espagnat’s emphases) [3].

This is where, I have argued, CM and QM inevitably lead us. But is the conception of any use? Or does it indicate something deeply wrong with the CM-QM partnership?

Maths with Everything

Here is a way in which it might help us. As everyone knows, modern physics is highly mathematical. Some outstanding physicists have expressed wonder at this, a notable example being Eugene Wigner in an article entitled ‘The Unreasonable Effectiveness of Mathematics in the Natural Sciences’ [4]. Why should it be that the abstract structures of mathematics should fit the world so well? It is not simply a matter of mathematics being some sort of abstract putty which could be moulded to any shape and so, inevitably, to the shape of the world. Those deeply involved in mathematical physics are struck by how it is the most conceptually elegant mathematics which happens to fit the world, and happens to fit with an accuracy way beyond what is needed to explain the original data. What could it be about the fundamental nature of the world which should make this so?

There is a bold conjecture which has been around for some time that perhaps the reason is that the material world is mathematical; is some sort of purely mathematical stuff. But it is an idea which has only ever slinked behind the scenes because it seems so unintelligible. What possible sense can be made of the idea that a magazine is a mathematical object?

If we think of mathematical objects such as numbers and multi-dimensional spaces as complete fictions, just picturesque ways of talking about an activity which in the end amounts only to playing games with ciphers, then there is no hope of making sense of the idea that a magazine is initself mathematical. But it is far from obvious that mathematics is that sort of game. Many mathematicians think that they are talking about real objects when they do mathematics and there are some forceful arguments that they are right. The question of the status of mathematical objects is very much a matter of dispute and, at the very least, there are no grounds as yet for dismissing the idea that mathematical objects are real things. Though when thought of as real they are normally considered to be abstract and not the furniture of material reality.

But it is when thinking of mathematical objects construed in this realistic way that the phenomenal/noumenal distinction might be applied effectively to understanding the mathematical nature of physical objects. A magazine could be a mathematical object in-itself so long as it were a physical object for-us. Our bodies could be physical objects for-us yet mathematical objects in-themselves. The seat of your consciousness now could be the mathematical object which is your body in-itself and which appears to you as a physical object. The causal link which appears to you to connect the magazine and your seeing of it, mediated by light, could be a mathematical link between the magazine in-itself and the bodily seat, in-itself, of the seeming seeing, mediated by the mathematical stuff which is light in-itself.

But mathematical things are not spatial and temporal, so how could your consciousness of here and now be because of a mathematical object, which is what I’m suggesting your body is in-itself? Well, space and time in-themselves could be mathematical and so the apparent spatiotemporal properties of things for-us could be some mathematical properties of those things in-themselves. What is here and now for you is the here and now of your body for-us; but the here and now of your body for-us could, in-itself, be a mathematical property of your body in-itself in relation to the world in-itself. Your consciousness of here and now is what it is like to be that body and your consciousness is the way it is, having a sense of here and now, because of the way your body is in-itself. There may be no reason why that way your body is should not be a mathematical way.

Perhaps this perspective strikes you as suffocating. What happens to all the world’s wide open spaces and tracts of time? They appear to be collapsed into an abstraction. I seem to be inviting us to believe that all the world’s grandeur is somehow written into something which is nothing like anything with which we are familiar. But all the wide open spaces really are safe. They are real enough according to the picture I have sketched. It is just that we ought not to enshrine the way they are for-us as the way they are inthemselves.

All I want to suggest is that it need not be as nonsensical as it might seem at first sight to think of material objects as being mathematical. But even if an idea like that were acceptable, wouldn’t it leave problematic what mathematical things really are? Of course it would. The philosophy of mathematics is a rich and complex field and nothing I have said aspires to making the nature of mathematics itself any clearer [5].

Notes :
1. Bertrand Russell, Nightmares of Eminent Persons, George Allen & Unwin, 1954.
2. René Descartes, A Discourse on Method, Meditations and Principles, J.M. Dent & Sons, 1986 p.84 (Meditation I).
3. Bernard d’Espagnat, Reality and the Physicist, Cambridge Univ. Press, 1989, p.15.
4. Eugene Wigner, Symmetries and Reflections, Indiana University Press, 1969.
5. I should like to thank my anonymous referee for some useful comments.

© Paul Tappenden 1991

Philosophy of Mind

This issue of Philosophy Now contains several articles which are concerned with the Philosophy of Mind. This branch of philosophy, dealing with the nature of the mind, and with its relationship with the physical world, has a terminology all of its own. As a public service, therefore, we provide this brief (and incomplete) glossary for the uninitiated.

Materialist : Someone who thinks that the physical world is all that there is, and that there are no such things as ghosts, souls, spirits etc.

Folk Psychology : A label for our everyday explanations of how people tick. Sometimes used in a slightly derogatory sense.

Eliminativist : A philosopher who wants to do away with all talk about minds which isn’t in terms of neurons, brain cells and so on. A materialist run amok.

Ordinary Language Philosopher : Someone who contends that because we talk about emotions (for instance), so there must be such things as emotions, ’cos otherwise we wouldn’t have words for them.

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