The Conscious Mind

The book that named the hard problem of consciousness and made it the organising question of a discipline. Its author argues that experience cannot be explained by anything physical, and proposes taking it as a fundamental feature of the world instead.

Date: 1996
Author: David Chalmers
Region: United States and Australia
Language: English

Where it stands in the argument

Position: Reply — Answers a named earlier work
Form: Treatise
Method: Analytic — Clarification of language and logical form
Transmission: Continuous — Copied and read without a break in its own language
Standing: Live — Still argued in current philosophical work
Years back to what it answers: 5 years

Gave a field its central question and its vocabulary within a few years, and made a position most philosophers reject impossible to ignore.

What the book says

A book built around a distinction that has since organised its whole field. The easy problems of consciousness are the ones about function: how a system discriminates stimuli, integrates information, reports its internal states, controls behaviour, distinguishes waking from sleep. These are hard in practice and there is no mystery about what a solution would look like - specify the mechanism and the problem is solved. The hard problem is different in kind. Why is any of that processing accompanied by experience? Why is there something it is like to see red, rather than the discrimination happening in the dark? Chalmers argues that no functional explanation can answer this, because for any function you specify, the question why it is experienced remains open. He supports the claim with the conceivability of a being physically identical to a person and wholly without experience - a philosophical zombie - and argues that if such a being is conceivable, consciousness does not logically follow from the physical facts. His own proposal is that experience should be taken as fundamental, like mass or charge, and related to physical processes by laws still to be discovered.

What it argues

That consciousness does not logically supervene on the physical, and that this requires expanding the inventory of what is fundamental rather than abandoning the physical sciences. The argument runs through conceivability: a world physically identical to ours but containing no experience seems coherently describable, whereas a world physically identical to ours in which water is not H2O does not - so the relation between the physical and the experiential is not the kind of relation that reduction handles. Chalmers is careful about what follows. He is not a dualist about substances, and the position he defends is naturalistic: experience would be a fundamental property, related to physical organisation by psychophysical laws, and the candidate principle he explores is that information has two aspects, one physical and one experiential, which leads toward panpsychism as a live option rather than an absurdity.

What it answered

Dennett directly, and the functionalist consensus of the previous thirty years. His deeper target is the assumption that philosophy of mind's remaining work is empirical - that once the neuroscience is done, the philosophical questions will have dissolved. The zombie argument is designed to show that a completed physical science would leave one question untouched, and the book's ambition is to make that question tractable rather than merely to insist on it.

How it argues

By careful sequential argument, with each move stated as a thesis and defended against listed objections. The first half is destructive and the second constructive, and the constructive half is what most critics ignore - Chalmers does not stop at declaring the problem hard but proposes a research programme, complete with candidate bridging principles and a discussion of what would count as evidence. The prose is precise, unhurried and free of rhetoric, and the book is easier than its subject.

The moment

The mid-1990s, with consciousness studies emerging as a self-conscious interdisciplinary field. Chalmers had trained in mathematics before philosophy, and the book's structure reflects it: the argument is laid out in numbered steps with objections anticipated in advance. The 1995 paper and the Tucson conferences that followed made the terminology general very quickly, and the phrase hard problem now appears well outside philosophy.

How it travelled

Fast and into several fields. The easy-hard distinction is now standard vocabulary in neuroscience, psychology and popular science writing; the zombie argument is taught in every philosophy of mind course; and panpsychism, which was a byword for absurdity in analytic philosophy, has become a position with serious defenders substantially because this book treated it as one. Chalmers' later work on the extended mind and on virtual reality has kept him unusually visible outside the discipline.

The strongest objection

That conceivability is not evidence of possibility, which is where nearly all the resistance concentrates. That a zombie world seems describable may show only that we have no idea how physical processing produces experience, and ignorance of a mechanism has never been a reason to think there is not one - people could once conceive of a physical duplicate of a living body that was not alive. Dennett's version is sharper: the zombie is not really conceivable at all, and anyone who thinks otherwise has simply not imagined the physical duplicate in enough detail. Chalmers' reply distinguishes kinds of conceivability with considerable care, and whether that machinery does the work is the central technical dispute in contemporary philosophy of mind.

Why read it

The first three chapters, which set out the distinction and the arguments and are the reason the book matters. The second half, on information and psychophysical laws, is more speculative and less read, and is worth knowing exists - the common criticism that Chalmers only poses a problem is not accurate. Read Dennett first; the two make sense as a pair.

Where to read it

First printed: 1996
First in English: 1996
Digitised: No

The 1995 paper Facing Up to the Problem of Consciousness introduced the easy-hard distinction and was published with responses from more than twenty philosophers and scientists, which is how the terminology spread.

Written in English and translated widely. In copyright.

Where it stands

Live and central. Most philosophers of mind reject the conclusion and almost all of them work in the terms the book set, which is an unusual kind of influence.

On quoting this book

In copyright. Nothing is quoted.

Contested

Whether zombies are genuinely conceivable, and whether conceivability licenses any conclusion about possibility, are the two standing questions and the whole argument turns on them. Whether the easy-hard distinction is a real division or a way of relabelling what has not yet been explained is disputed by those who expect the hard problem to dissolve as the science advances. And whether Chalmers' own positive proposal is a theory or a placeholder is questioned even by philosophers sympathetic to the negative argument.