The claim of this paper is that the everyday functions of knowledge make most sense if we see knowledge as contrastive. That is, we can best understand how the concept does what it does by thinking in terms of a relation “a knows that p rather than q.” There is always a contrast with an alternative. Contrastive interpretations of knowledge, and objections to them, have become fairly common in recent philosophy. The version defended here is fairly mild in that there (...) is no suggestion that we cannot think in terms of a simpler not explicitly contrastive relation “a knows that p.” Some, for instance Schaffer (2005) and Karjalainen and Morton (2003), have hinted that this stronger possibility may be right. But all that I am arguing now is that facts that are easily expressed in contrastive terms are vital to understanding why we need the concept of knowledge. In a piece that is in some ways a companion to this one ("Contrastivism" in Duncan Pritchard and Sven Bernecker, eds. The Routledge Companion to Epistemology. Routledge 2010, 513-522), I give a general survey of theories of contrastive knowledge and the differences between them. (shrink)

General contrastivism holds that all claims of reasons are relative to contrast classes. This approach applies to explanation (reasons why things happen), moral philosophy (reasons for action), and epistemology (reasons for belief), and it illuminates moral dilemmas, free will, and the grue paradox. In epistemology, contrast classes point toward an account of justified belief that is compatible with reliabilism and other externalisms. Contrast classes also provide a model for Pyrrhonian scepticism based on suspending belief about which contrast class is relevant. (...) This view contrasts with contextualism, invariantism, and Schaffer's contrastivism. (shrink)

We describe the three place relation of contrastive knowledge, which holds between a person, a target proposition, and a contrasting proposition. The person knows that p rather than that q. We argue for three claims about this relation. (a) Many common sense and philosophical ascriptions of knowledge can be understood in terms of it. (b) Its application is subject to fewer complications than non-contrastive knowledge is. (c) It applies over a wide range of human and nonhuman cases.

Contextualism treats ‘knows’ as an indexical that denotes different epistemic properties in different contexts. Contrastivism treats ‘knows’ as denoting a ternary relation with a slot for a contrast proposition. I will argue that contrastivism resolves the main philosophical problems of contextualism, by employing a better linguistic model. Contextualist insights are best understood by contrastivist theory.

Subject sensitive invariantism is the view that whether a subject knows depends on what is at stake for that subject: the truth-value of a knowledge-attribution is sensitive to the subject's practical interests. I argue that subject sensitive invariantism cannot accept a very plausible principle for memory to transmit knowledge. I argue, furthermore, that semantic contextualism and contrastivism can accept this plausible principle for memory to transmit knowledge. I conclude that semantic contextualism and contrastivism are in a dialectical position better than (...) subject sensitive invariantism is. (shrink)

Radical skepticism, the view that no human being has any contingent knowledge of any external world there may be, has few adherents these days. But many who reject it concede that such skeptical arguments as SA require some sort of response, since they are obviously valid and their premises are, at the very least, highly plausible.

Does what you know depend on what is at stake for you? That is, is the knowledge relation sensitive to the subject’s practical interests? Subject sensitive invariantists (Fantl and McGrath, 2002; Hawthorne, 2004, ch. 4; Stanley, forthcoming) say that the answer is yes. They claim to capture the contextualist data without the shifty semantics. I will argue that the answer is no. The knowledge relation is sensitive to what is in question for the attributor, rather than what is at stake (...) for the subject. There is no substitute for the contextualist semantics. (shrink)