Living with UncertaintY

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Czech translation of this article

The pain of being uncertain

There seems to be something within most of us that craves certainty. It may indeed be hard-wired within our brain; some theories of the perception mechanism are based on the idea that it works by resolving ambiguities. You've probably seen those drawings which could be viewed as the head of either a young girl or an old woman.

Ambiguous image

You can see one or the other at a time but not both. Other pictures seem to be made up of random splotches, until suddenly you see a semi-concealed figure

Hidden figure

What is significant about such images is that, once you've seen the hidden picture, you can't un-see it; your visual system has been changed for ever. Perhaps the belief system works in a similar kind of way, so that once a belief has been adopted, it becomes difficult to dislodge.

At any rate, most of us do seem to want to adopt firm views about things, or at least about things that matter to us deeply. We feel uncomfortable when we have to suspend judgement, even when there is insufficient evidence to reach a firm conclusion. And very often we seem to adopt beliefs for reasons that are unknown to us. It may even be the case that they are always unknown to us, and that the reasons we give ourselves for believing, say, in God, or in the extra-terrestrial origins of UFOs, or in Freudian psychoanalysis are always rationalizations.

Libet's experiments

I am thinking here about some fascinating experiments which were carried out about 15 years ago by a neurosurgeon called Benjamin Libet. He was interested in discovering how the conscious decision to initiate an action was related to electrical changes in the brain. His subjects had electrodes attached to their wrists to pick up movements, and to their scalps to pick up the electrical activity of their brains. They watched a revolving spot on a clock face. Their task was to flex their wrist at some moment of their own choosing, and to note where the spot was on the clock face at that instant. Libet recorded three events: the start of the action (flexing the wrist), the moment of the conscious decision to move, and the start of a particular brain wave pattern called a readiness potential.

What Libet found was that the readiness potential began just over half a second (550 milliseconds) before the action, and the decision to act about a fifth of a second (200 milliseconds) before the action. In other words, the brain change came first and the conscious decision second. This is a difficult result to explain if you believe in dualism (separate mind and brain). There has been a lot of controversy over this work and Libet himself is unwilling to admit what appear to be its full implications (he thinks that the "self" may be able to inhibit an action although it does not initiate it), but there is no doubt that there is something important here to be explained.

How we form beliefs

It seems likely that something similar happens in the brain in the case of belief. In other words, changes occur in our brains before we adopt a belief and we are then presented with the result, which we try to justify to ourselves as best we can. But the reasons we give ourselves to explain why we believe things may well be wrong.

The philosopher Daniel Dennett has written extensively on this view of the mind. Forming a belief could be thought of as a means of resolving a conflict in the mind. When you are undecided about something there is a sensation of discomfort, presumably produced by a mismatch between two different patterns of activity in the brain; when these are reconciled a belief is generated and the discomfort is relieved. But this neurological process is unconscious and can never be accessed by introspection.

If I reflect on changes in fundamental beliefs that have occurred in my own life, I find that I cannot easily account for them, or can do so only in a roundabout way by citing factors that may be irrelevant. I started life as a Roman Catholic, and until my early twenties I remained fully convinced of the rightness of our religion. Indeed, the only thing that puzzled me was why, since we were so obviously right, the rest of the country didn't convert to Catholicism straight away. My eventual loss of faith was seemingly quite sudden.

My experience of the process

When I was about 23 I used to have long conversations with a friend from school who was undergoing doubts about religion. I used to argue with him from what I assumed was my firm basis in Catholicism, but within a short time I found that I didn't believe what I was saying. It didn't take long before I had argued myself, not just out of belief in Catholicism, but out of belief in Christianity as a whole.

However, I remained a vague theist for many years and it was a long time before I felt able to look squarely at the thought that I might actually be an atheist. In part this was because I became involved in a different metaphysical system, this time of Eastern provenance, which for a time acted as a kind of substitute belief system for the Catholicism of my youth. Eventually, however, I ceased to believe in that as well, although not with the dramatic suddenness that had characterized my loss of faith in Catholicism.

I should say that the predominant feeling that accompanied these and other similar disappearances of belief in my life was not one of loss but rather of liberation. I've generally experienced belief systems as a burden, though not at the time I held them, but only after shedding them. (A burden, because I kept coming across facts which seemed to threaten the belief systems in question and required increasingly difficult intellectual contortions to resolve.) Doubtless this is an individual quirk of character, but I can't believe I'm unique in that respect. Over the years I've found that I'm generally happier without the metaphysical beliefs of my earlier years; the more I shed them, the more comfortable I feel.

Adopting naturalism as my view

Nowadays I'm content to subscribe to what have been called the tenets of naturalism. I find no problem with the thought that we are the products of Darwinian natural selection, which implies that we have come into existence contingently and not as the result of any Divine Plan. There is no immaterial soul hovering over the body, and there is nothing of us to survive physical death. The only valid knowledge we can have comes to us through the kind of rational inquiry we call science, and not through religion or revelation.

I cannot prove this way of thinking to be true, and I recognize that there are other people, quite as rational as I and equally or more intelligent, who think differently. But, for whatever reasons, my particular brain throws up this pattern of thinking and not another. (Ironically enough, this way of looking at the process of belief formation echoes the Catholic doctrine that faith is a gift from God; either He gives it to you or He doesn't, and there's nothing you can do about it.)

Never forget to doubt your own opinions

Yet although I find I'm more at ease within the rationalist camp than outside it, I do recognize that there is within rationalism an unfortunate tendency to smugness, which often seems to to characterize the pronouncements of certain sceptical organizations such as CSIOP (Committee for Scientific Investigation of the Paranormal). No doubt such critics are right to say that we are today in considerable danger of being swamped by a tsunami of irrationality, but often they seem to go further than this and imply that the present scientific consensus about the world is pretty well the last word on the subject; we have arrived at final truth.

A little humility seems in order here. The astronomer and cosmologist Fred Hoyle has reminded us that it's not so long since practically all astronomers were convinced that our galaxy was the whole Universe. What blinkers may we still be wearing today without realizing it? It's impossible to know what scientists a hundred years hence will think of the views we hold today, but it's difficult not to imagine that they will be as amused and surprised by our scientific prejudices and errors as are we when we read about some of the opinions of scientists at the beginning of the twentieth century.

As the biologist J.B.S. Haldane famously remarked, the universe is not only queerer than we suppose, it is queerer than we can suppose. We should not totally discount the possibility that we could be mistaken at a fundamental level. The world could be quite different from how it seems to us. We are contingent beings, with brains that are modified ape brains that evolved to cope with practical problems such as avoiding predators and finding food and mates; it is remarkable that these brains can also do science and speculate about metaphysical questions, but there is no guarantee that there aren't all sorts of things they can't cope with. Perhaps there are things we can't conceive of at all. A cat may look at a king, but it can form no notion of kingship.

Keeping a balance

The danger in saying things like this is that so many people will take it as a licence to believe whatever they want. After all, they say, if science has been wrong about so many things in the past, why not about astrology, say, or healing crystals, or the extra-terrestrial origin of UFOs? The range of crazy ideas that might just be right is almost limitless; no one can look into them all. So how do we distinguish between the really crazy ideas and the only seemingly crazy?

It's notoriously difficult to make such a distinction. Probably the classic example of this is Wegener's theory of continental drift. What could be madder than to suppose that the continents, far from being immutably anchored, are really slipping and sliding around on the surface of the earth and crashing into one another? All right-thinking geologists confidently dismissed this notion as too silly to discuss when Wegener put it forward in the 1920s, yet today it is the cornerstone of geology. If continental drift can become accepted by mainstream science, where are we to draw the line?

And yet we do have to draw lines, if we are not to be submerged in the sea of irrationality. I'm fully persuaded that the principle of systematic doubt, which first appeared in ancient Greece and resurfaced in the West in the Enlightenment, is the only guide we should trust. But we should trust it fully; we should always be ready to question the foundations of our own beliefs.

Bertrand Russell tells the story of a lecturer in mathematics who wrote up a proof on the board. A student raised his hand and objected, saying that there was an error in the calculation. The lecturer stopped for a moment and re-read what he had written. "You're right," he said; "I've been doing the proof that way for years, but it was wrong." Russell says that the audience's respect for the lecturer was greatly enhanced by this admission of error. However difficult psychologically it may be to follow this man's example, I am sure it is the duty of true rationalists to do so.

See also The Casaubon Delusion, Avoiding the Casaubon Delusion, and The Fine Art of Skepticism


  • Libet B., 1985. `Unconscious cerebral initiative and the role of conscious will in voluntary action'. Behaviour and Brain Sciences, 8, 229-266, including commentaries following this article.
  • Libet B., 1999. `Do we have free will?'. Journal of Consciousness Studies, 6, 47-57.
  • Daniel C. Dennett (1992). Consciousness Explained. Viking, London.