Online research in philosophy

The book concludes with a qualified defence of the view that honesty is a virtue.

CONTRASTING PREJUDICES TRUTH AND FALSEHOOD How can one say something false? How can one even think such a thing? Since, for example, all men are mortal, ...

Classically, truth and falsehood are opposite, and so are logical truth and logical falsehood. In this paper we imagine a situation in which the opposition is so pervasive in the language we use as to threaten the very possibility of telling truth from falsehood. The example exploits a suggestion of Ramsey’s to the effect that negation can be expressed simply by writing the negated sentence upside down. The difference between ‘p’ and ‘~~p’ disappears, the principle of double negation becomes trivial, and the truth/falsehood opposition is up for grabs. Our moral is that this indeterminacy undermines the idea of inferential role semantics.

In his 1963 article, “Is Justified True Belief Knowledge?”1 Edmund Gettier devised a pair of counterexamples designed to illustrate that knowledge cannot be adequately defined as justified true belief. The basic idea behind both of his counterexamples is that one can be justified in believing a falsehood P from which one deduces a truth Q, in which case one has a justified true belief in Q but does not know Q. Gettier’s article inspired numerous other counterexamples, and the search was on for a fourth condition of knowledge, one that could be added to justification, truth, and belief to produce an adequate analysis of knowledge.

It is useful to note how (CC) differs from closure: (C) If S comes to believe q solely on the basis of competent deduction from p and S knows that p, then S knows that q. I won’t be discussing (C) today, but here is a useful contrast.

Falsehood can preclude knowledge in many ways. A false proposition cannot be known. A false ground can prevent knowledge of a truth, or so we argue, but not every false ground deprives its subject of knowledge. A falsehood that is not a ground for belief can also prevent knowledge of a truth. This paper provides a systematic account of just when falsehood precludes knowledge, and hence when it does not. We present the paper as an approach to the Gettier problem and arrive at a relatively simple theory with virtues linked to several issues at the heart of contemporary epistemology.