In Reason, Truth, and History Hilary Putnam has presented an anti-skeptical argument purporting to prove that we are not brains in a vat. How exactly the argument goes is somewhat controversial. A number of competing "recon¬structions" have been proposed. They suffer from a defect which they share with what seems to be Putnam's own version of the argument. In this paper, I examine a very simple and rather natural reconstruction of the argument, one that does not employ any premises in (...) which a sentence, viz. the sentence 'I am a brain in a vat', is mentioned rather than used. In this respect my version of the argument is importantly different from what appears to be Putnam's own version. (shrink)

This paper compares two kinds of epistemic principles---an underdetermination principle and a deductive closure principle. It argues that each principle provides the basis for an independently motivated skeptical argument. It examines the logical relations between the premises of the two kinds of skeptical argument and concludes that the deductive closure argument cannot be refuted without refuting the underdetermination argument. The underdetermination argument, however, can be refuted without refuting the deductive closure argument. In this respect, the deductive closure argument is the (...) stronger of the two. (shrink)

This paper defends the legitimacy of semantical responses to certain skeptical challenges, with a particular focus on Putnam’s treatment of a particular version of Brain-in-Vat skepticism. It argues that while Putnam’s argument does not provide a general reply to Brain-in-Vat skepticism, the general approach it exemplifies is actually crucial in replying to other skeptical challenges that are otherwise hard to rebut.

The sceptic about the external world presents us with a paradox: an apparently acceptable argument for an apparently unacceptable conclusion—that we do not know anything about the external world. Some paradoxes, for instance the liar and the sorites, are very hard. The defense of a purported solution to either of these two inevitably deploys the latest in high-tech philosophical weaponry. On the other hand, some paradoxes are not at all hard, and may be resolved without much fuss. They do not (...) contain profound lessons about the human condition. Where should we place the sceptical paradoxes? (shrink)

Much has been written about epistemological skepticism in the last ten or so years, but there remain some unanswered questions concerning the structure of what has become the canonical Cartesian skeptical argument. In this paper, I would like to take a closer look at this structure in order to determine just which epistemic principles are required by the argument.

In "Externalism, Self-Knowledge and Skepticism,"' Kevin Falvey and Joseph Owens argue that externalism with respect to mental content does not engender skepticism about knowledge of content. They go on to argue that even when externalism is freed from epistemological difficulties, the thesis cannot be used against Cartesian skepticism about knowledge of the external world. I would like to raise some questions about these claims.

This is a response to a recent Philosophical Studies article by Bredo Johnsen, in which he makes a number of criticisms of Putnamian anti-skeptical arguments.

In chapter 1 of Reason, Truth, and History, Hilary Putnam argues from some plausible assumptions about the nature of reference to the conclusion that it is not possible that all sentient creatures are brains in a vat. If this argument is successful, it seemingly refutes an updated form of Cartesian skepticism concerning knowledge of physical objects. In this paper, I will state what I take to be the most promising interpretation of Putnam's argument. My reconstructed argument differs from an argument (...) strongly suggested by Putnam's text. I will show that the latter argument obviously does not work. The more promising argument which I reconstruct on behalf of Putnam raises some interesting questions about the relation between the contents of one's beliefs and one's environment and about how this relation affects the evaluation of anti-skeptical arguments. I conclude that my reconstructed argument ultimately fails as a response to Cartesian skepticism: the argument engenders a skepticism about knowledge of meaning, or propositional content, which undercuts its anti-skeptical force. (shrink)

Hilary Putnam has offered two arguments to show that we cannotbe brains in a vat, and one to show that our cognitive situationcannot be fully analogous to that of brains in a vat. The latterand one of the former are irreparably flawed by misapplicationsof, or mistaken inferences from, his semantic externalism; thethird yields only a simple logical truth. The metaphysical realismthat is Putnams ultimate target is perfectly consistent withsemantic externalism.

This paper argues that, given a certain apparently inevitable thesis about content, we could not know our own minds. The thesis is that the content of a thought is determined by its relational properties.

Knowledge and its Limits presents a systematic new conception of knowledge as a kind of mental stage sensitive to the knower's environment. It makes a major contribution to the debate between externalist and internalist philosophies of mind, and breaks radically with the epistemological tradition of analyzing knowledge in terms of true belief. The theory casts new light on such philosophical problems as scepticism, evidence, probability and assertion, realism and anti-realism, and the limits of what can be known. The arguments are (...) illustrated by rigorous models based on epistemic logic and probability theory. The result is a new way of doing epistemology and a notable contribution to the philosophy of mind. (shrink)

Crispin Wright; IV*—On Putnam's Proof that We are not Brains-in-a-Vat1, Proceedings of the Aristotelian Society, Volume 92, Issue 1, 1 June 1992, Pages 67–94, h.

If it works, I can use Putnam’s vat argument to show that I have not always been a brain-in-a-vat. It is widely thought that the vat argument is of no use against closure scepticism – that is, scepticism motivated by arguments that appeal to a closure principle. This is because, even if I can use the vat argument to show that I have not always been a BIV, I cannot use it to show that I was not recently envatted, and (...) it is thought that the claim that I am not justified in thinking that I was not recently envatted is all that the closure sceptic requires. In this paper I first argue that scenarios in which I have been recently envatted are inadequate for the sceptic’s purposes, and so the standard argument that the vat argument is of no use against closure scepticism fails. I then argue that it is not possible to revise the standard argument to meet my objection. I conclude that, if it works, I can use the vat argument as a defence against closure scepticism. (shrink)

Hilary Putnam deals in this book with some of the most fundamental persistent problems in philosophy: the nature of truth, knowledge and rationality. His aim is to break down the fixed categories of thought which have always appeared to define and constrain the permissible solutions to these problems.

UNCLEAR as it is, the traditional doctrine that the notion "meaning" possesses the extension/intension ambiguity has certain typical consequences. The doctrine that the meaning of a term is a concept carried the implication that mean- ings are mental entities. Frege, however, rebelled against this "psy- chologism." Feeling that meanings are public property-that the same meaning can be "grasped" by more than one person and by persons at different times-he identified concepts (and hence "intensions" or meanings) with abstract entities rather than (...) mental entities. However, "grasping" these abstract entities was still an individual psychological act. None of these philosophers doubted that understanding a word (knowing its intension) was just a matter of being in a certain psychological state (somewhat in the way in which knowing how to factor numbers in one's head is just a mat- ter of being in a certain very complex psychological state). (shrink)

Human beings have the unique ability to view the world in a detached way: We can think about the world in terms that transcend our own experience or interest, and consider the world from a vantage point that is, in Nagel's words, "nowhere in particular". At the same time, each of us is a particular person in a particular place, each with his own "personal" view of the world, a view that we can recognize as just one aspect of the (...) whole. How do we reconcile these two standpoints--intellectually, morally, and practically? To what extent are they irreconcilable and to what extent can they be integrated? Thomas Nagel's ambitious and lively book tackles this fundamental issue, arguing that our divided nature is the root of a whole range of philosophical problems, touching, as it does, every aspect of human life. He deals with its manifestations in such fields of philosophy as: the mind-body problem, personal identity, knowledge and skepticism, thought and reality, free will, ethics, the relation between moral and other values, the meaning of life, and death. Excessive objectification has been a malady of recent analytic philosophy, claims Nagel, it has led to implausible forms of reductionism in the philosophy of mind and elsewhere. The solution is not to inhibit the objectifying impulse, but to insist that it learn to live alongside the internal perspectives that cannot be either discarded or objectified. Reconciliation between the two standpoints, in the end, is not always possible. (shrink)

Hilary Putnam has offered two arguments to show that we cannotbe brains in a vat, and one to show that our cognitive situationcannot be fully analogous to that of brains in a vat. The latterand one of the former are irreparably flawed by misapplicationsof, or mistaken inferences from, his semantic externalism; thethird yields only a simple logical truth. The metaphysical realismthat is Putnam’s ultimate target is perfectly consistent withsemantic externalism.

Psychological externalism is the thesis that the contents of many of a person's propositional mental states are determined in part by relations he bears to his natural and social environment. This thesis has recently been thrust into prominence in the philosophy of mind by a series of thought experiments due to Hilary Putnam and Tyler Burge. Externalism is a metaphysical thesis, but in this work I investigate its implications for the epistemology of the mental. I am primarily concerned with the (...) question whether externalism undermines the idea that a person typically knows the contents of her own thoughts, beliefs, and other propositional attitudes directly and authoritatively. I criticize arguments that have been advanced on behalf of a positive answer to this question, and argue that they rest on a faulty conception of the nature of first person authority, one which likens our access to our own minds to perception. An account of the basis of first person authority is sketched that locates our epistemic right to our self-ascriptions of propositional attitude not in our ability to discriminate among the various thought contents we might be thinking, but rather in our ability to express our thoughts, and to think with them in accordance with the norms of rationality. I consider also the question whether first person authority and externalism jointly make possible a refutation of certain forms of global skepticism, as has been famously argued by Putnam. I argue that Putnam's attempted refutation fails, because the crucial externalist claims that drive it are not knowable a priori. (shrink)

This paperback edition reproduces the complete text of the Essay as prepared by professor Nidditch for The Clarendon Edition of the Works of John Locke. The Register of Formal Variants and the Glossary are omitted and Professor Nidditch has written a new foreword.

Hilary Putnam deals in this book with some of the most fundamental persistent problems in philosophy: the nature of truth, knowledge and rationality. His aim is to break down the fixed categories of thought which have always appeared to define and constrain the permissible solutions to these problems.

Tim Button explores the relationship between words and world; between semantics and scepticism. -/- A certain kind of philosopher – the external realist – worries that appearances might be radically deceptive. For example, she allows that we might all be brains in vats, stimulated by an infernal machine. But anyone who entertains the possibility of radical deception must also entertain a further worry: that all of our thoughts are totally contentless. That worry is just incoherent. -/- We cannot, then, be (...) external realists, who worry about the possibility of radical deception. Equally, however, we cannot be internal realists, who reject all possibility of deception. We must position ourselves somewhere between internal realism and external realism, but we cannot hope to say exactly where. We must be realists, for what that is worth, and realists within limits. -/- In establishing these claims, The Limits of Realism critically explores and develops several themes from Hilary Putnam’s work: the model-theoretic arguments; the connection between truth and justification; the brain-in-vat argument; semantic externalism; and conceptual relativity. The book establishes the continued significance of these topics for all philosophers interested in mind, logic, language, or the possibility of metaphysics. (shrink)