Exhibition: Philosophy in the Open

Mind and Brain

Anthony Quinton and Charles Taylor start off by discussing the question in their title: whether the mind is identical to the brain. But somehow they end up discussing a rather different question: whether all mental things can be explained in neural or biological terms. Since they don’t actually tell us that they have changed topic, this is a little confusing.

Quinton starts boldly with the idea that for ‘every kind of mental event’ there is something correlated with it in the brain; and then adds that where you find such correlations, you might as well say that the ‘correlated things’ are identical. Taylor points out that we actually don’t know this for most of the things we call mental events or states (e.g. complex states like worrying about your reputation).

Quinton immediately backs down and concedes that we don’t know the neural correlations for these very complex states or events, but that we should start with the simple ones we do know about, and build up from there. His approach is then to pass the burden of proof to Taylor: what is about the identity theory you don’t like, then? Overall, his general line is that we know that the brain affects the mind, so we should assume they are identical as we now do with phenomena like lightning: there aren’t two things, the lightning and the electrical discharge. There is just one. So it should be with the mind and the brain.

Today’s materialists can do better. They could appeal to the causal arguments of David Lewis and David Armstrong (1966 and 1968 respectively). Broadly speaking, these arguments start from two assumptions: that the distinctive character of mental states is their causal role, and that we know that all physical effects have physical causes. With some additions of premises and weakening of the two assumptions, as shown by David Papineau (in work published from 1990 onwards), materialists can now use a general philosophical argument for the identity theory, without having to appeal to hypothesised ‘correlations’.

The dialogue took place in 1972, so Quinton could have been familiar with Lewis’s and Armstrong’s work. But perhaps ideas took longer to cross the oceans in those days. However, one idea which may have influenced Taylor is Davidson’s influential claim in ‘Mental Events’ (1970) that even if individual mental events are identical with neural events, this does not mean that these events can be given wholly neural explanations. Or perhaps the influence was the other way around: Davidson quotes Taylor (semi-) approvingly in his 1970 paper; and recall too that Taylor’s anti-reductionist book, The Explanation of Behaviour, was published in 1964.

Whatever the direction of influence, Taylor moves the debate with Quinton away from the question of identity to the question of explanation. Can all mental activity be explained in neuroscientific terms? Taylor explicitly says no, and even concedes that humans are wholly physical systems. Having bypassed (or maybe conceded for the sake of argument) the question of identity, Taylor makes a good case for the ineliminable nature of our mental explanations and the mental vocabulary.

While protesting that this may just be because it is all a bit too complex, Quinton essentially agrees. It’s just a shame that they could not have told us, at some point during this charming dialogue, that they were changing the subject.

Tim Crane

Tim Crane is Professor Philosophy at the Central European University in Vienna.

Related videos and essays (all links open in a new window)

• Other Minds: A. J. Ayer and Godfrey Vesey discuss the problem of other minds.
  Accompanying essay by Anita Avramides.
• Free Will: Geoffrey Warnock and psychologist B. F. Skinner discuss free will and determinism.
  Accompanying essay by Daniel C. Dennett.
• The Concept of Mind: Gilbert Ryle and Susan Haack discuss Ryle’s work on the mind.
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• Perception: Rodney Hirst and Alan White discuss perception.
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• Personal Identity: Sidney Shoemaker and Hywell Lewis discuss the question of identity. Accompanying essay by Amy Kind.