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What is the mind?
sharpened by Descartes, 1641· Big question· Reality, mind & God
Mostly agreedGood evidence; some details uncertain.
The question of what minds are, how thoughts and feelings relate to the brain, and whether matter alone can explain them.
See it on the Philosophy map →The idea
Main answers. Dualism: mind and body are different substances (Descartes). Dual-aspect monism: one reality seen two ways (Spinoza). Idealism: only minds and ideas are basic (Berkeley). Materialism or physicalism: the mind is what the brain does (Hobbes then, most scientists now). Functionalism: mind is like software, defined by what it does, not what it is made of. The sticking point, which David Chalmers named the 'hard problem' in 1994: why brain activity feels like anything from the inside.
Why it matters
The answer decides whether animals, AI or a damaged brain can have minds, and what, if anything, could survive death.
Where it comes from
Plato's Phaedo and Aristotle's On the Soul began the debate; Descartes' Meditations (1641) set its modern terms, and brain science now supplies data any answer must fit.
Still debated
There is no agreed account of how physical processes produce conscious experience; even whether the 'hard problem' is a real problem is disputed.
Connections (5)
▸René Descartes sharpened What is the mind?Mostly agreed
The connection
Before Descartes, most thinkers, following Aristotle, treated the soul as the form or life of the body. By splitting thinking mind from mechanical body, Descartes turned the question into a sharp puzzle: how two utterly different things interact, and what consciousness is in a world of matter.
When and how
Meditations on First Philosophy, Paris, 1641, and Passions of the Soul, 1649, debated across Europe through his printed objections and letters.
How sure are we?
Philosophy-of-mind textbooks start with Descartes, and 'Cartesian dualism' names the view most later theories define themselves against.
Debates and open questions
Some argue Descartes invented a false problem by separating mind and body at all; others say he only made an old puzzle explicit.
▸Mind–body dualism gives one classic answer to What is the mind?Mostly agreed
The connection
Dualism is the classic answer to what the mind is: an immaterial thinking substance, distinct from the brain and body. It fits common intuitions and many religious views of the soul, but its interaction problem pushed most later philosophers toward materialism or other alternatives.
When and how
Descartes' Meditations (1641); predecessors include Plato's Phaedo, and philosophers such as Richard Swinburne still defend versions today.
How sure are we?
In the 2020 PhilPapers survey of philosophers, about half favored physicalism and about a third non-physicalism, a camp broader than Descartes' substance dualism.
Debates and open questions
Property dualism, which says brains have non-physical properties such as experience, keeps a version alive; whether any dualism fits neuroscience is debated.
▸Turing's imitation game ("Can machines think?") gave a behavioural test for What is the mind?Mostly agreed
The connection
Instead of defining 'mind' or 'thinking', Turing proposed judging by behavior: if a machine converses as well as a person, deny it a mind only if you would deny one to people, whom we also judge by behavior. This shifted the old question of mind toward what a system does, not what it is made of.
When and how
Turing, at the University of Manchester, published the proposal in the philosophy journal Mind in October 1950.
How sure are we?
The paper is explicit, and it set off a long debate in philosophy of mind, feeding functionalism and provoking Searle's Chinese Room (1980).
Debates and open questions
Whether behavior can ever settle the question is the core dispute: critics say a system could pass while understanding or feeling nothing.
▸Chalmers and the hard problem of consciousness sharpened What is the mind?Well documented
The connection
Chalmers split 'What is the mind?' into two parts: how the brain processes information, which science is steadily answering, and why that processing is felt at all, which it is not. The split showed exactly where materialist answers struggle, and it is now the standard way to frame the question.
When and how
Tucson, Arizona, at the first 'Toward a Science of Consciousness' conference in 1994; published in 1995.
How we know
The term is used across philosophy and neuroscience; in the 2020 PhilPapers survey about 62% of philosophers accepted or leaned toward there being a hard problem.
Debates and open questions
Illusionists such as Keith Frankish argue the problem rests on a mistaken picture of experience; whether it is a real problem is itself contested.
▸Thomas Nagel, "What Is It Like to Be a Bat?" showed the subjective side of What is the mind?Mostly agreed
The connection
Theories of mind in the 1960s, like the identity theory and functionalism, explained mental states as brain events or causal roles. Nagel argued these leave out the subjective character of experience, so any answer to 'What is the mind?' must account for it or admit what it misses.
When and how
The Philosophical Review, October 1974, amid debates over identity theory and functionalism led by J. J. C. Smart, David Armstrong and Hilary Putnam.
How sure are we?
It is among the most-reprinted essays in philosophy of mind, and supporters and critics alike treat 'what it is like' as the mark of consciousness.
Debates and open questions
Some philosophers, such as Daniel Dennett, argue Nagel overstated the gap and that science can tell us a lot about what it is like to be a bat.