Hilary Putnam
What our words mean depends partly on the world and our community, not only on what is inside our heads.
Placement
Brains in a vat and Twin Earth: “Meanings just ain't in the head.”
Key ideas
- Semantic externalism
- Functionalism
- Internal realism
Teachers: Hans Reichenbach
Students: Jerry Fodor
Influence
Influenced by 7
William James
influenced by ✓
Putnam took up James’s natural realism about perception and his pragmatism, which joins fallibilism with antiscepticism (‘James’s Theory of Perception’, 1990; Pragmatism: An Open Question, 1995). H. Putnam, “James’s Theory of Perception”, in Realism with a Human Face (1990); Pragmatism: An Open Question (1995); SEP “William James”
William James › 1842–1910
John Dewey
influenced by ✓
Putnam took up Dewey’s experimental view of democracy and his rejection of a fact–value dichotomy (‘A Reconsideration of Deweyan Democracy’, 1990; The Collapse of the Fact/Value Dichotomy, 2002). H. Putnam, “A Reconsideration of Deweyan Democracy”, Southern California Law Review 63 (1990), in Renewing Philosophy (1992); The Collapse of the Fact/Value Dichotomy (2002); SEP “John Dewey”
John Dewey › 1859–1952
Ludwig Wittgenstein
influenced by ✓
Putnam drew on Wittgenstein, read not as an anti-realist, for his natural realism of perception and his account of religious language (Renewing Philosophy, 1992; The Threefold Cord, 1999). H. Putnam, Renewing Philosophy (1992); The Threefold Cord: Mind, Body, and World (1999); “Was Wittgenstein Really an Anti-realist about Mathematics?” (2001)
Ludwig Wittgenstein › 1889–1951
Rudolf Carnap
influenced by
Putnam, who worked with Carnap on inductive logic (1953–54), illustrated his conceptual relativity with a ‘Carnapian’ world of three individuals (The Many Faces of Realism, 1987). H. Putnam, The Many Faces of Realism (1987); “‘Degree of Confirmation’ and Inductive Logic”, in P. A. Schilpp (ed.), The Philosophy of Rudolf Carnap (1963); SEP “Rudolf Carnap”
Evidence: AI draft
Rudolf Carnap › 1891–1970
Hans Reichenbach studied with
studied with
Putnam took his PhD at UCLA in 1951 under Reichenbach with a dissertation on the meaning of the concept of probability in application to finite sequences. H. Putnam, The Meaning of the Concept of Probability in Application to Finite Sequences (diss. UCLA 1951; printed 1990)
Evidence: also in InPhO · InPhO
Hans Reichenbach › 1891–1953
W. V. O. Quine
influenced by
Putnam developed Quine’s point that mathematics is indispensable to science into an argument for mathematical realism (Philosophy of Logic, 1971), known as the Quine–Putnam indispensability argument. H. Putnam, Philosophy of Logic (1971); “The Analytic and the Synthetic” (1962); SEP “Indispensability Arguments in the Philosophy of Mathematics”
Evidence: also in InPhO · InPhO
W. V. O. Quine › 1908–2000
Alan Turing
influenced by
Putnam modelled mental states on the states of a Turing machine, founding machine functionalism (‘Minds and Machines’, 1960; ‘Psychological Predicates’, 1967). H. Putnam, “Minds and Machines”, in S. Hook (ed.), Dimensions of Mind (1960); “Psychological Predicates” (1967), repr. as “The Nature of Mental States”; SEP “Functionalism”
Evidence: also in InPhO · InPhO
Alan Turing › 1912–1954
Influenced 2
Jerry Fodor taught
taught
Fodor took his PhD at Princeton in 1960 under Putnam with a dissertation in the philosophy of language, The Uses of ‘Use’. Mathematics Genealogy Project, entry J. A. Fodor (Princeton 1960)
Evidence: also in InPhO · InPhO
Jerry Fodor › 1935–2017
Alice Crary
influenced
Crary, whose Harvard undergraduate thesis Putnam supervised, shared his rejection of the fact–value dichotomy, arguing that moral concepts reveal real features of the world (Beyond Moral Judgment, 2007). A. Crary, Beyond Moral Judgment (2007); H. Putnam, The Collapse of the Fact/Value Dichotomy (2002)
Evidence: AI draft
Alice Crary › b. 1967
Criticism
Criticizes 3
René Descartes
criticised
Putnam argued that the brain-in-a-vat hypothesis, a modern version of Descartes’ demon, refutes itself: envatted brains could not even refer to vats (Reason, Truth and History, 1981). H. Putnam, Reason, Truth and History (1981), ch. 1 “Brains in a Vat”; R. Descartes, Meditationes (1641), I
Evidence: AI draft
René Descartes › 1596–1650
Gottlob Frege
criticised
Putnam’s Twin Earth case denied that the Fregean sense a speaker grasps fixes a term’s extension: ‘meanings just ain’t in the head’ (‘The Meaning of “Meaning”’, 1975). H. Putnam, “The Meaning of ‘Meaning’”, Minnesota Studies in the Philosophy of Science 7 (1975), 131–193
Evidence: AI draft
Gottlob Frege › 1848–1925
J. J. C. Smart
criticised
Putnam objected to Smart’s identity of sensations and brain processes that pain can be realised in different systems, so mental states are functional states (‘Psychological Predicates’, 1967). H. Putnam, “Psychological Predicates” (1967), repr. as “The Nature of Mental States”; J. J. C. Smart, “Sensations and Brain Processes”, Philosophical Review 68 (1959)
Evidence: AI draft
J. J. C. Smart › 1920–2012
Works
Twin Earth: meanings just ain't in the head.
Brains in a vat – and why we cannot be such brains.
Position
Putnam shaped several debates at once. In philosophy of mind he proposed functionalism: mental states are defined by their causal role, not by the material that realises them – which is why minds could in principle run on different “hardware.” In philosophy of language his Twin Earth thought experiment showed that what our words mean depends on the world and the linguistic community, not only on what is in our heads: “meanings just ain’t in the head.” Later he turned against metaphysical realism and argued with the “brains in a vat” scenario that the sceptical hypothesis refutes itself. Putnam’s path from scientific realism to a pragmatist “internal realism” makes him one of the most stimulating thinkers of analytic philosophy.
Life & context
Putnam was born in Chicago in 1926 and took his doctorate at UCLA under Hans Reichenbach. After teaching at Princeton and MIT he spent most of his career at Harvard from 1965. He worked across mathematical logic, philosophy of science, mind and language, and was known for openly revising his own positions; he was also politically active in the 1960s.
Further main works
- Minds and Machines (1960)
- Representation and Reality (1988)
Appears in
- Journey ‘The Riddle of Consciousness’ · Stop 6 of 10
- Debate ‘Can Machines Think or Feel?’
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