This is a preprint of a book chapter. The final version was published in The Routledge companion to epistemology, edited by Sven Bernecker and Duncan Pritchard; New York: Routledge, 2011.In his classic (1953) article, Richard Rudner claims that "in accepting a hypothesis the scientist must make the decision that the evidence is sufficiently strong or that the probability is sufficiently high to warrant the acceptance of the hypothesis. Obviously, our decision regarding the evidence and respecting how strong is 'strong enough', is going to be a function of the importance, in the typically ethical sense, of making a mistake in accepting or rejecting the hypothesis… How sure we need to be before we accept a hypothesis will depend on how serious a mistake would be." According to Rudner, an adequate account of the conditions of warranted hypothesis acceptance must include reference to an ethical or more broadly a pragmatic factor. Rudner explicitly confines his discussion to the evidence or probability needed to be warranted in accepting a hypothesis, where acceptance for him seems to be subject to voluntary control, at least in certain cases: we decide the evidence is sufficiently strong. But in the past decade a number of philosophers have offered views similar to Rudner's about a broader range of epistemic concepts. For example, regarding knowledge, Jeremy Fantl and Matthew McGrath ((2002) and (2007)), John Hawthorne (2004), and Jason Stanley (2005) have recommended views according to which, whether a subject knows something to be the case depends on their practical situation
