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Hilary W. Putnam (born July 31, 1926) has been a central figure in Western philosophy for the last fifty or sixty years, particulary in philosophy of mind, philosophy of language, and philosophy of science. He is perhaps best known, not so much for any particular view, but for his willingness to approach all philosophical positions, his own included, with the same degree of intense scrutiny, subjecting them to rigorous analysis until he has exposed their flaws. As a result, he has acquired a reputation for frequently changing his mind.

In philosophy of mind, Putnam is known for his hypothesis of multiple realizability, and for the concept of functionalism, a new and influential theory in the mind-body problem, though one that he himself went on to reject. In philosophy of language, along with Saul Kripke and others, he developed the causal theory of reference, and formulated an original theory of meaning, inventing the notion of semantic externalism based on a famous thought experiment called Twin Earth.

In philosophy of mathematics, along with his mentor W.V.O. Quine, Putnam developed an argument for the reality of mathematical entities that became known as the "Quine-Putnam indispensibility thesis", later espousing the view that mathematics is not purely logical, but "quasi-empirical". In the field of epistemology, he is known for another famous thought experiment called brain in a vat and its challenge to epistemological skepticism. In metaphysics, he originally espoused a position called metaphysical realism, inevitably becoming one of its most outspoken critics, and adopting a view he called "internal realism". He eventually abandoned that too, moving to a position of pragmatist-inspired direct realism, which aims to return the study of metaphysics to the way people actually experience the world, by rejecting the idea of mental representations, sense data, and other intermediaries between mind and world.

Outside philosophy, Putnam has made contributions to mathematics and computer science. He developed the Davis-Putnam algorithm for the Boolean satisfiability problem, with Martin Davis, and contributed to the solution of Hilbert's tenth problem.

Biography

Hilary Whitehall Putnam was born in Chicago, Illinois in 1926. His father, Samuel Putnam, was a well-known author and translator. His mother, Riva, was a homemaker. Though she was Jewish, Putnam was raised as an atheist because of his father's firm commitment to Communism. Putnam grew up in France, where his parents lived until 1934. After moving with his family to Philadelphia in 1935, he went on to receive his AB (undergraduate degree) from the University of Pennsylvania. He was a member of the Philomathean Society, the oldest US literary society. In 1951, he received a PhD from UCLA under Hans Reichenbach with a thesis entitled "The Meaning of the Concept of Probability in Application to Finite Sequences". His teachers, Rudolf Carnap and Hans Reichenbach, were among the leaders of logical positivism, the dominant school of early 20th century American philosophy.

After brief teaching stints at Northwestern, Princeton, and MIT, he moved to Harvard University in 1965 with his wife, Ruth Anna Putnam, who also took a teaching position in philosophy at MIT. Hilary and Ruth Anna were married in 1962. Ruth Anna was born in Munich, Germany in 1927 to anti-Nazi political-activist parents and, like Putnam himself, she was raised an atheist. The Putnam's, rebelling against their common upbringing and against the pervasive atmosphere of anti-semitism of the time, decided to establish a traditional Jewish home for their children. Since they had no experience of the rituals of Judaism, they sought out invitations to other Jew's homes for Seder. They had "no idea how to do it ", in the words of Ruth Anna. So, they began to study Jewish ritual and Hebrew. In 1994, Hilary Putnam celebrated his belated bar mitzvah. His wife celebrated her bat mitzvah four years later.

Putnam was one of the most popular teachers on campus at Harvard and, in keeping with the family tradition, he was also one of the most politically active. In 1976 he was elected President of the American Philosophical Association. The following year, he was selected as Walter Beverly Pearson Professor of Mathematical Logic, in recognition of his contributions to the philosophy of logic and mathematics.

During the period of his most productive philosophical activity, Putnam got involved in political movements in the United States. In the late 1960s and early 1970s, he was a very active opponent of American military intervention in Vietnam and a strong supporter of civil rights causes. In 1963, he organized one of the first faculty and student committees against the war at MIT. He publicly expressed his outrage against the reporting of David Halberstam. For example, he was disturbed by Halberstam's claim that the U.S. was "defending" South Vietnamese peasants from the Vietcong by poisoning their rice crops. After moving to Harvard in 1965, he organized various campus protests and began teaching courses on Marxism. He became an official faculty advisor to the Students for a Democratic Society and eventually became a member of the Progressive Labor Party (PLP).

After 1968 most of his political activities were directed through the PLP. At one point, Harvard University attempted to censure Putnam for such activities because the university administration considered them disruptive, but he succeeded in rallying large numbers of friends and supporters to defeat this attempt. Putnam permanently severed his ties with the PLP in 1972. In 1997, at a meeting of former draft resistance activists at Arlington Street Church in Boston, Putnam described his involvement with the PLP as a mistake. He said he had at first been impressed with PLP's commitment to alliance-building and its willingness to attempt to organize from within the armed forces. While breaking with his radical past, Putnam has never abandoned his belief that academics have a particular social and ethical responsibility toward society. He has continued to be forthright and progressive in his political views, as expressed in the articles "How Not to Solve Ethical Problems" (1983) and "Education for Democracy" (1993).

Professor Putnam is a Fellow of the American Academy of Arts and Sciences, and a Corresponding Fellow of the British Academy. He retired from teaching in June of 2000. He is currently the Cogan University Professor Emeritus at Harvard University. His immense corpus includes five volumes of collected works, seven books, and over 200 articles. Putnam's strongly renewed interest in Judaism has motivated him to publish several recent books and essays on the topic. Along with his wife, he has also published several books and essays on the late 19th century American pragmatist movement.

Philosophy of mind

Multiple realizability

Putnam is most well-known for his original contributions to the philosophy of mind, such as his formulation of the hypothesis of multiple realizability. The locus classicus of the thesis of multiple realizability is to be found in several papers published by Putnam in the late 1960's. In these papers, he argued that, contrary to the famous claim of the type-identity theory, it is not necessarily true that "pain is identical to C-fibre firing." It is quite possible, and indeed probable, that pain corresponds to completely different physical states of the nervous system in different organisms and yet they all experience the same mental state of "being in pain." Putnam cited examples from all over the animal kingdom to illustrate his thesis. Is it likely, he asked, that the brain structures of all mammals, reptiles, birds, amphibians and molluscs realize pain, or other mental states, in exactly the same way? Do they even have the same brain structures? Clearly not, if we are to believe the evidence furnished by comparative neuroanatomy and neurophysiology. How is it possible then that they can share the same mental states and properties? The answer had to be that these mental states were realized by different physical states in different species. Putnam then took his argument a step further, asking about such things as the nervous systems of alien beings, artificially-intelligent robots and silicon-based life forms. Should such hypothetical entities be considered a priori incapable of experiencing pain just because they do not have the same neurochemistry as humans? Putnam concluded that type-identity theorists had been making an extremely "ambitious" and "highly implausible" conjecture which could be disproven with just one example of multiple realizability. This is sometimes referred to as the likelihood argument.

Putnam also formulated a complementary argument based on what he called functional isomorphism. He defined the concept in these terms: "Two systems are functionally isomorphic if there is a correspondence between the states of one and the states of the other that preserves functional relations." So, in the case of computers, two machines are functionally isomorphic if and only if the sequential relations among states in the first are exactly mirrored by the sequential relations among states in the other. Therefore, a computer made out of silicon chips and a computer made out of cogs and wheels can be functionally isomorphic but constitutionally diverse. Functional isomorphism implies multiple realizability. This is sometimes referred to as an "a priori argument".

Jerry Fodor, Putnam, and others soon noted that, along with being a very effective argument against type-identity theories, multiple realizability implied that any low-level explanation of higher-level mental phenomena would be insufficiently abstract and general. Functionalism, which identifies mental kinds with functional kinds that are characterized exclusively in terms of causes and effects, abstracts from the level of microphysics and hence it seemed to be a better explanation of the relation between mind and body. In fact, there are many functional kinds, such as mousetraps, software and bookshelves, which are multiply realized at the physical level.

Machine state functionalism

The first formulation of such a functionalist theory was put forth by Putnam himself. This formulation, which is now called machine-state functionalism, was inspired by analogies which Putnam and others noted between the mind and the theoretical "machines" (or computers) capable of computing any given algorithm which were developed by Alan Turing (called universal Turing machines).

In non-technical terms, a Turing machine can be visualized as an infinitely long tape divided into squares (the memory) with a box-shaped scanning device that sits over and scans one square of the memory at a time. Each square is either blank (B) or has a 1 written on it. These are the inputs to the machine. The possible outputs are:

• Halt: Do nothing.
• R: move one square to the right.
• L: move one square to the left.
• B: erase whatever is on the square.
• 1: erase whatever is on the square and print a 1.

An extremely simple example of a Turing machine which writes out the sequence '111' after scanning three blank squares and then stopping is specified by the following machine table:

This table states that if the machine is in state one and scans a blank square (B), it will print a 1 and remain in state one. If it is in state one and reads a 1, it will move one square to the right and also go into state two. If it is in state two and reads a B, it will print a 1 and stay in state two. If it's in state two and reads a 1, it will move one square to the right and go into state three. Finally, if it is in state three and reads a B, it prints a 1 and remains in state three.

The essential point to consider here is the nature of the states of the Turing machine. Each state can be defined in terms of its relations to the other states as well as inputs and outputs. State one, for example, is simply the state in which the machine, if it reads a B, writes a 1 and stays in that state, and in which, if it reads a 1, it moves one square to the right and goes into a different state. This is the functional definition of state one; it is its causal role in the overall system. The details of how it accomplishes what it accomplishes and of its material constitution are completely irrelevant.

According to machine-state functionalism, the nature of a mental state is just like the nature of the automaton states described above. Just as state one simply is the state in which, given an input B, such and such happens, so being in pain is the state which disposes one to cry "ouch", become distracted, wonder what the cause is, and so forth.

Rejection of functionalism

In more recent years, Putnam has abandoned his adherence to functionalism and other computational theories of the mind. This is primarily due to the enormous difficulties which such theories have in dealing with intuitions about the externalism of mental content as illustrated through Putnam's own Twin Earth thought experiment (see philosophy of language). He also developed a separate argument in 1988, based on Fodor's generalized version of multiple realizability, against functionalism. Noting that functionalism is just a watered-down reductionist or identity theory in which mental kinds are ultimately identified with functional kinds, Putnam argued that mental kinds were probably multiply realizable over functional kinds. The same mental state or property could be implemented or realized by different states of a universal Turing machine.

Philosophy of language

Semantic externalism

One of Putnam's most significant contributions to the philosophy of language is his doctrine that "meaning just ain't in the head", which is illustrated by his Twin Earth thought experiment. Concisely, he argues that if you see a liquid and call it "water" and some alien twin of yours (identical down to the last detail) on an alien planet sees what appears to be an identical liquid and calls it water AND if it turns out it was really XYZ and not H₂O, then you and your double actually mean something different by water even though water has the same function for both of you. This led Putnam to adopt a version of semantic externalism with regard to meaning and mental content.

Theory of meaning

Along with Saul Kripke, Keith Donnellan and others, Putnam made important contributions to what is known as the causal theory of reference.

In particular, Putnam maintains in The Meaning of "Meaning" that the objects referred to by natural kind terms (such as tiger, water, tree, and so on) are the principle elements of the meaning of such terms. There is a linguistic division of labor (analogous to Adam Smith's economic division of labor) according to which such terms have their references fixed by the "experts" in the particular field of science to which the terms belongs. So, for example, the reference of the term lion is fixed by the community of zoologists, the reference of the term elm tree is fixed by the community of botanists, the reference of the term table salt is fixed as NaCl by chemists, and so on. These referents are considered rigid designators in the Kripkean sense and are then disseminated outward to the linguistic community at large.

Putnam then specifies "a normal form (or, rather, a type of normal form) for the description of the meaning" of every term in the language. Such a "normal form" consists in a finite sequence - or vector - whose components are:

1. the object to which the term refers (the object individuated by the chemical formula H₂O, for example)
2. a set of characteristic descriptions (called the stereotype) such as for example transparent, colorless, hydrating, etc.
3. the semantic indicators which place the object into a general category (e.g., natural kind, liquid, etc.) and
4. the syntactic indicators (concrete noun, mass noun, etc.).

Such a normal form offers a description of the reference and use of an expression within a particular linguistic community, providing explicit conditions for its correct usage and making it possible to judge whether a single speaker attributes to the expression E the appropriate meaning, or whether the use of E has undergone a transformation within the community significant enough to determine a semantic change. It is legitimate, according to Putnam, to speak of a change in meaning of an expression only if the reference of the term has changed and not its stereotype. But since there is no possible algorithm which can determine which aspect, the stereotype or the reference, has changed in a particular instance, it is necessary to consider the usage of other expressions of the language. Since there is no limit, in principle, to the number of such expressions which must be considered, Putnam embraces a form of semantic holism.

Philosophy of mathematics

One of Putnam's contributions to the philosophy of mathematics is the so-called Quine-Putnam indispensability argument for mathematical realism (or mathematical platonism). This argument is considered by Steven Yablo, among others, to be one of the most challenging arguments in favor of the acceptance of the actual existence of abstract mathematical entities, such as numbers and sets. The form of the argument is extremely simple:

(a) We must have ontological commitments to all and only the entities that are indispensable to our best scientific theories.

(b) Mathemathical entities are indispensable to our best scientific theories.

Ergo, (c) We must have ontological commitments to mathematical entities.

The justification for the first premise is the most controversial. Both Putnam and Quine invoke naturalism to justify the elimination of all non-scientific or supernatural entities, and hence to defend the only part of all and only in the first premise. The assertion that all entities quantified over in scientific theories, including numbers, should be accepted as real is justified through the invocation of confirmation holism. Since theories are not confirmed in an atomistic and piecemeal fashion but as a whole, there seems be no logical justification for excluding any of the entities postulated by well-confirmed theories. This puts the nominalist who wishes to exclude the existence of sets and non-Euclidean geometry but include the existence of quarks and other postulated but undetectable entities of physics, for example, in a very difficult position.

Putnam also holds the view that in mathematics, as in physics and other empirical sciences, not only strict logical proofs, but rather, while not doing this explicitly, "quasi-empirical" methods are used. That is, methods like verifying by many calculations that for no integer n > 2 do there exist positive integer values of x, y, and z such that x + y = z (Fermat's last theorem proved in 1995 by Andrew Wiles). Even if we treat such knowledge as more conjectural than a strictly proven theorem, we still make use of it in developing mathematical ideas that are based on it.

Mathematics and computer science

Putnam is noted for several contributions to scientific fields not directly related to his work in philosophy. As a mathematician, Putnam contributed to the resolution of Hilbert's tenth problem in mathematics. Yuri Matiyasevich had formulated a theorem involving the use of Fibonacci numbers in 1970 which was designed to answer the question of whether there is a general algorithm that can decide whether a given system of Diophantine equations (polynomials with integer coefficents) has a solution among the integers. Putnam, working with Martin Davis and Julia Robinson, demonstrated that Matiyasevich's theorem was sufficient to prove that no such general algorithm can exist. It was therefore shown that David Hilbert's famous tenth problem has no solution.

In computer science, Putnam is known for the Davis-Putnam algorithm for the Boolean satisfiability problem (SAT), developed with Martin Davis in 1960. The algorithm finds if there is a set of true or false values that satisfies a given Boolean expression so that the entire expression becomes true. In 1962 they further refined the algorithm with the help of George Logemann and Donald W. Loveland. It became known as the DPLL algorithm. This algorithm is highly efficient and still forms the basis for most complete SAT solvers today.

Epistemology

Putnam is known in the field of epistemology for a thought experiment known as the "Brain in a Vat", which is interpreted by several philosophers, such as Tim Black, as an attempt at a refutation of skepticism. The argument is that you cannot coherently state that you are a "brain in a vat" placed there by a "mad scientist" (an old science fiction cliché, as seen in the movie Dark City, and also an allusion to Descartes' Evil Genius).

This is a result of the causal theory of reference. Words always refer to the kinds of things they were coined to refer to, thus the kinds of things their user, or her ancestors, experienced. So, if some person, Mary, was indeed a "brain in a vat", whose every experience is received through wiring and other gadgetry created by the "mad scientist", then Mary's idea of a "brain" would not refer to a "real" brain, since she and her linguistic community have never seen such a thing. Rather she saw something that looked like a brain, but was actually an image fed to her through the wiring. Similarly, her idea of a "vat" would not refer to a "real" vat. So, if, as a "brain in a vat", she were to say "I'm a brain in a vat", she would actually mean to say "I'm a brain-image in a vat-image", which is incoherent. If, on the other hand, she is not a "brain in a vat", then saying that she is is still incoherent, but this time because she actually means the opposite. This is a form of epistemological externalism: knowledge or justification depends on factors outside of the mind or intellect and is not simply determined internally.

With Putnam's argument, though one is unable to be a brain in a vat, one is still able to be a 'brain in a vat'. Putnam's argument depends on no access to an underlying reality which leaves the evident world the same as the true world. The argument fails to establish that there is no underlying reality, though, so one is still able to be a 'brain in a vat'.

Philosophy of science and ontology

In the latter part of the 1980's and 1990's, Putnam abandoned his longstanding defence of, what he came to call, metaphysical realism, the view that the categories and structures of the external world are both causally and ontologically independent of the conceptualizations of the human mind. Instead he adopted a rather different view which he called internal realism or pragmatic realism.

Internal realism is essentially the view that, though the world is indeed causally independent of the human mind, the structure of the world - its division into kinds, individuals and categories - is a function of the human mind, and hence the world is not ontologically independent. The general idea is substantially influenced by Kant's idea of the dependence of our knowledge of the world on the categories of thought.

The problem with metaphysical realism, according to Putnam, is that it fails to explain the possibility of reference and truth. According to the metaphysical realist, our concepts and categories refer because they match up in some mysterious manner with the pre-structured categories, kinds and individuals that are inherent in the external world. But how is it possible that the world "carves up" into certain structures and categories, the mind carves up the world into its own categories and structures, and the two "carvings" perfectly coincide? The answer must be that the world does not come pre-structured but that structure must be imposed on it by the human mind and its conceptual schemes.

Major works

• Philosophy of Mathematics: Selected Readings. Edited with Paul Benacerraf. Englewood Cliffs, N.J.: Prentice-Hall, 1964. 2nd ed., Cambridge: Cambridge University Press, 1983.
• Philosophy of Logic. New York: Harper and Row, 1971. London: George Allen and Unwin, 1972.
• Mathematics, Matter and Method. Philosophical Papers, vol. 1. Cambridge: Cambridge University Press, 1975. 2nd. ed., 1985.
• Mind, Language and Reality. Philosophical Papers, vol. 2. Cambridge: Cambridge University Press, 1975.
• Meaning and the Moral Sciences. London: Routledge and Kegan Paul, 1978.
• Reason, Truth, and History. Cambridge: Cambridge University Press, 1981.
• Realism and Reason. Philosophical Papers, vol. 3. Cambridge: Cambridge University Press, 1983.
• Methodology, Epistemology, and Philosophy of Science: Essays in Honour of Wolfgang Stegmüller. Edited with Wilhelm K. Essler and Carl G. Hempel. Dordrecht: D. Reidel, 1983.
• Epistemology, Methodology, and Philosophy of Science: Essays in Honour of Carl G. Hempel. Edited with Wilhelm K. Essler and Wolfgang Stegmüller. Dordrecht: D. Reidel, 1985.
• The Many Faces of Realism. La Salle, Ill.: Open Court, 1987.
• Representation and Reality. Cambridge, Mass.: MIT Press, 1988.
• Realism with a Human Face. Edited by James Conant. Cambridge, Mass.: Harvard University Press, 1990.
• Renewing Philosophy. Cambridge, Mass.: Harvard University Press, 1992.
• Pursuits of Reason: Essays in Honor of Stanley Cavell. Edited with Ted Cohen and Paul Guyer. Lubbock: Texas Tech University Press, 1993.
• Words and Life. Edited by James Conant. Cambridge, Mass.: Harvard University Press, 1994.
• Pragmatism: An Open Question. Oxford: Blackwell, 1995.
• The Threefold Cord: Mind, Body, and World. New York: Columbia University Press, 1999.
• Enlightenment and Pragmatism. Assen: Koninklijke Van Gorcum, 2001. 48pp.
• The Collapse of the Fact/Value Dichotomy and Other Essays. Cambridge, Mass.: Harvard University Press, 2002.
• Ethics Without Ontology. Cambridge, Mass.: Harvard University Press, 2004.

Works about Putnam

• P. Clark-B. Hale (eds.), "Reading Putnam", Blackwell, Cambridge (Massachusetts)-Oxford 1995.
• C.S. Hill (ed.), "The Philosophy of Hilary Putnam", Fayetteville, Arkansas 1992.
• M. Rudel, "Erkenntnistheorie und Pragmatik: Untersuchungen zu Richard Rorty und Hilary Putnam", Hamburg 1987.

References

1. ^ Casati R., "Hillary Putnam" in Enciclopedia Garzanti della Filosofia, ed. Gianni Vattimo. 2004. Garzanti Editori. Milan. ISBN 8811505151
2. Putnam, H. One Hundred Philosophers: The Life and Work of the World's Greatest Thinkers. Barron's 2004, p. 170.
3. "TPM:Philosopher of the Month".
4. LeDoux, J. (2002). The Synaptic Self;How Our Brains Become Who We Are. New York: Viking Penguin. {{cite book}}: Text "ISBN 8870787958" ignored (help)
5. ^ P. Clark-B. Hale (eds.), "Reading Putnam", Blackwell, Cambridge (Massachusetts)-Oxford 1995.
6. Colyvan, Mark, "Indispensability Arguments in the Philosophy of Mathematics", The Stanford Encyclopedia of Philosophy (Fall 2004 Edition), Edward N. Zalta (ed.),http://plato.stanford.edu/archives/fall2004/entries/mathphil-indis/
7. ^ Putnam, H. Philosophy of Mathematics: Selected Readings. Edited with Paul Benacerraf. Englewood Cliffs, N.J.: Prentice-Hall, 1964. 2nd ed., Cambridge: Cambridge University Press, 1983. Cite error: The named reference "PutBen" was defined multiple times with different content (see the help page).
8. ^ Putnam, H. Realism with a Human Face. Edited by James Conant. Cambridge, Mass.: Harvard University Press, 1990.
9. ^ Putnam,H. The Threefold Cord: Mind, Body, and World. New York: Columbia University Press, 1999.
10. ^ Davis, M. and Putnam, H. "A computing procedure for quantification theory" in Journal of the ACM, 7:201–215, 1960.
11. ^ Matiyesavic, Yuri. "Hilbert's Tenth Problem".
12. "Curriculum Vitae".
13. ^ Hickey, L.P. "Hilary Putnam".
14. ^ Foley, M. "Book review:Confronting the War Machine".
15. "Crimson article on Putnam and Harvard admin".
16. "New York Times correction".
17. ^ Putnam, H. (1975)Mind, Language and Reality. Philosophical Papers, vol. 2. Cambridge: Cambridge University Press, 1975. ISBN 8845902579
18. ^ Bickle, John "Multiple Realizability", The Stanford Encyclopedia of Philosophy (Fall 2006 Edition), Edward N. Zalta (ed.),URL=http://plato.stanford.edu/archives/fall2006/entries/multiple-realizability/
19. Fodor, J. (1974) "Special Sciences" in Synthese, 28, pp. 97-115
20. Fodor, J. (1980) "The Mind-Body Problem", Scientific American, 244, pp. 124-132
21. ^ C.S. Hill (ed.), "The Philosophy of Hilary Putnam", Fayetteville, Arkansas 1992.
22. Sipser, M. (1997) Introduction to the Theory of Computation. PWS Publishing Company. Boston, Mass. ISBN 053494728X
23. Block, Ned. "What is Functionalism".
24. Putnam, Hilary (1988). Representation and Reality. Cambridge, MA: MIT Press.
25. ^ Putnam, H. (1981): "Brains in a vat" in Reason, Truth, and History, Cambridge University Press; reprinted in DeRose and Warfield, editors (1999): Skepticism: A Contemporary Reader, Oxford UP.
26. Dell'Utri, Massimo. (2002) Olismo. Quodlibet. Macerata. ISBN 8886570856
27. Yablo, S. "A Paradox of Existence".
28. ^ Putnam, H. Mathematics, Matter and Method. Philosophical Papers, vol. 1. Cambridge: Cambridge University Press, 1975. 2nd. ed., 1985.
29. "Wiles summary".
30. Black, T. ""A Moorean Response to Brain-in-a-Vat Skepticism" (PDF).
31. P. Clark-B. Hale (eds.), "Reading Putnam", Blackwell, Cambridge (Massachusetts)-Oxford 1995.
32. Putnam, H. The Many Faces of Realism. La Salle, Ill.: Open Court, 1987.
33. Curtis Brown. "Internal Realism:Transcendental Idealism?".

External links

• Philosopher Olaf L Müller's elaboration of the Brain in a Vat argument
• The God Problem recording of a discussion with Alvin Plantinga on The Connection radio show.
• Hilary Putnam's homepage at Harvard.
• Putnam's draft resistance work
• Harvard Crimson article on Putnam's criticism of Harvard administration; see also others: ,
• An extensive bibliography for Hilary Putnam

• 1926 births
• Living people
• 20th century philosophers
• American philosophers
• Analytic philosophers
• Pragmatists
• University of Pennsylvania alumni
• Philosophers of mind
• Jewish philosophers