Multiple realisability
If the same pain could occur in creatures with very different physical structures, one fixed brain-state identity may be too narrow.
Twentieth-century philosophy · 1920–2012
Smart
Smart proposes that sensations are brain processes described in another vocabulary, removing the need for a second mental substance or dangling properties.
John Jamieson Carswell Smart was a British-Australian philosopher who worked across philosophy of mind, science, time, religion and ethics. He became a leading defender of mind-brain identity theory and of act utilitarianism.
MindEthicsKnowledge
The question he enters
The question Smart enters
Could a sensation and a brain process be one event described in two very different ways?
The central move
Identify experience with the brain process
Smart argues that reports of sensations can be topic-neutral: they identify what is happening without committing to a separate mental substance. Scientific inquiry may then discover that the event is a brain process, just as lightning is discovered to be an electrical discharge rather than something correlated with one.
Key ideas
Terms that carry the argument.
- Type identity theory
- The view that kinds of conscious state are identical with kinds of brain process.
- Topic-neutral analysis
- A way of describing experience by its occurrence and effects without assuming whether its nature is mental or physical.
- Nomological danglers
- Irreducible mental properties that would sit awkwardly outside an otherwise unified physical account of nature.
- Act utilitarianism
- The view that each action should be assessed by whether it produces the best consequences available.
Where the view strains
Objections and limits.
The explanatory gap remains
Discovering a correlation or identity claim may not explain why that process has the felt quality it does.
Sources and routes
Read the work. Follow the argument.
Primary texts
Where to meet the position.
- JSTORSensations and Brain ProcessesWebThe classic statement of mind-brain identity theory and topic-neutral analysis.The Philosophical Review, volume 68, number 2, April 1959, pages 141–156. · Stable journal record; full-text access may depend on an institution or personal account. Checked Aug 2026.
- Open LibraryPhilosophy and Scientific RealismWebA naturalistic metaphysics shaped by science, physicalism and parsimony.Work-level library catalogue record for Philosophy and Scientific Realism; select a listed edition on the record. · Bibliographic record with edition, library-location, borrowing or preview links where available; this row is bibliographic or sample-only unless the selected edition states otherwise. Checked Aug 2026.
- Open LibraryUtilitarianism: For and AgainstWebSmart's defence of act utilitarianism paired with Bernard Williams's criticism.Work-level library catalogue record for Utilitarianism; for and against; select a listed edition on the record. · Bibliographic record with edition, library-location, borrowing or preview links where available; this row is bibliographic or sample-only unless the selected edition states otherwise. Checked Aug 2026.
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