How fallacious is the consequence fallacy?
In Williamson (2007) , Timothy Williamson argues against "the tactic of criticizing confidence in a theory by identifying a logical consequence of the theory (not itself a logical truth) whose probability is not raised by the evidence" (232-233). He dubs it the consequence fallacy. In this paper, we will show that Williamson"s formulation of the tactic in question is ambiguous. On one reading of Williamson"s formulation, the tactic is indeed a fallacy, but it is not a commonly used tactic; on
... other reading, it is a commonly used tactic (or at least more often used than the former tactic), but it is not a fallacy. The two readings of Williamson"s formulation of the tactic are: (T1) Arguing that the probability of a theory is not raised by the evidence by identifying a logical consequence of the theory whose probability is not raised by the evidence. (T2) Arguing that a theory is not made likely to be true by the evidence by identifying a logical consequence of the theory that is not made likely to be true by the evidence. 1 Williamson"s use of the phrase "probability is not raised" suggests (T1), while his use of the word "confidence" suggests (T2). (T1) is a fallacy, but Williamson"s argument for its fallaciousness, though ingenious, is not completely satisfying. We will explain the weaknesses in his argument and try to improve on it. We will also show that (T2) is not a fallacy and explain why it is a more commonly used tactic than (T1). Williamson"s argument for the fallaciousness of the consequence fallacy now understood as (T1) is brief. Consider a theory h and evidence e. Assume that e is evidence for h in the sense that it raises the probability of h, although it does not make h certain. In symbols, Forthcoming in Philosophical Studies