The book was planned and written as a single, sustained argument. But earlier versions of a few parts of it have appeared separately. The object of this book is both to establish the existence of the paradoxes, and also to describe a non-Pascalian concept of probability in terms of which one can analyse the structure of forensic proof without giving rise to such typical signs of theoretical misfit. Neither the complementational principle for negation nor the multiplicative principle for conjunction applies (...) to the central core of any forensic proof in the Anglo-American legal system. There are four parts included in this book. Accordingly, these parts have been written in such a way that they may be read in different orders by different kinds of reader. (shrink)

This article described three heuristics that are employed in making judgements under uncertainty: representativeness, which is usually employed when people are asked to judge the probability that an object or event A belongs to class or process B; availability of instances or scenarios, which is often employed when people are asked to assess the frequency of a class or the plausibility of a particular development; and adjustment from an anchor, which is usually employed in numerical prediction when a relevant value (...) is available. These heuristics are highly economical and usually effective, but they lead to systematic and predictable errors. A better understanding of these heuristics and of the biases to which they lead could improve judgements and decisions in situations of uncertainty. (shrink)

This essay grows out of the conviction that recent work by psychologists studying human reasoning has important implications for a broad range of philosophical issues. To illustrate our thesis we focus on Nelson Goodman's elegant and influential attempt to "dissolve" the problem of induction. In the first section of the paper we sketch Goodman's account of what it is for a rule of inference to be justified. We then marshal empirical evidence indicating that, on Goodman's account of justification, patently invalid (...) inferential rules turn out to be "justified." We conclude that something is seriously wrong with Goodman's story about justification. In the second section we attempt to patch Goodman's account. The notion of epistemic authority and the social aspect of justification play central roles in the alternative account of justification that we propose. (shrink)

The end of the nineteenth century is remembered as a time when psychology freed itself from philosophy and carved out an autonomous subject matter for itself. In fact, this time of emancipation was also a time of exile: while the psychologists were leaving, philosophers were slamming the door behind them. Frege is celebrated for having demonstrated the irrelevance of psychological considerations to philosophy. Some of Frege’s reasons for distinguishing psychological questions from philosophical ones were sound, but one of Frege’s most (...) influential arguments, which was elaborated upon and advocated by the positivists, vastly overestimated the gap separating the two disciplines. (shrink)

I wish to advocate a reorientation of epistemology. Lest anyone maintain that the enterprise I urge is not epistemology at all (even part of epistemology), I call this enterprise by a slightly different name: epistemics. Despite this terminological concession, I believe that the inquiry I advocate is significantly continuous with traditional epistemology. Like much of past epistemology, it would seek to regulate or guide our intellectual activities. It would try to lay down principles or suggestions for how to conduct our (...) cognitive affairs. The contrast with traditional epistemology – at least "analytic" epistemology of the twentieth century – would be its close alliance with the psychology of cognition. The basic premise of epistemics is that one cannot give the best advice about intellectual operations without detailed information about mental processes. Since these processes are most illuminatingly studied by cognitive psychology, epistemics would go hand in hand with empirical investigation of our "information-processing" mechanisms. (shrink)

The object of this paper is to show why recent research in the psychology of deductive and probabilistic reasoning does not have.