Confirmation is commonly identified with positive relevance, E being said to confirm H if and only if E increases the probability of H. Today, analyses of this general kind are usually Bayesian ones that take the relevant probabilities to be subjective. I argue that these subjective Bayesian analyses are irremediably flawed. In their place I propose a relevance analysis that makes confirmation objective and which, I show, avoids the flaws of the subjective analyses. What I am proposing is in some (...) ways a return to Carnap's conception of confirmation, though there are also important differences between my analysis and his. My analysis includes new accounts of what evidence is and of the indexicality of confirmation claims. Finally, I defend my analysis against Achinstein's criticisms of the relevance concept of confirmation. (shrink)

Peter Achinstein has argued at length and on many occasions that the view according to which evidential support is defined in terms of probability-raising faces serious counterexamples and, hence, should be abandoned. Proponents of the positive probabilistic relevance view have remained unconvinced. The debate seems to be in a deadlock. This paper is an attempt to move the debate forward and revisit some of the central claims within this debate. My conclusion here will be that while Achinstein may be right (...) that his counterexamples undermine probabilistic relevance views of what it is for e to be evidence that h, there is still room for a defence of a related probabilistic view about an increase in being supported, according to which, if p > p, then h is more supported given e than it is without e. My argument relies crucially on an insight from recent work on the linguistics of gradable adjectives. (shrink)

This paper addresses two examples due to Peter Achinstein purporting to show that the positive relevance view of evidence is too strong, that is, that evidence need not raise the probability of what it is evidence for. The first example can work only if it makes a false assumption. The second example fails because what Achinstein claims is evidence is redundant with information we already have. Without these examples Achinstein is left without motivation for his account of evidence, which uses (...) the concept of explanation in addition to that of probability. (shrink)

An amended bootstrapping can avoid Christensen's counterexamples. Earman and Edidin argue that Christensen's examples to bootstrapping rely on his failure to analyze background knowledge. I add an additional condition to bootstrapping that is motivated by Glymour's remarks on variety of evidence. I argue that it avoids the problems that the examples raise. I defend the modification against the charge that it is holistic, and that it collapses into Bayesianism.

This paper attempts to clarify the meaning and significance of "qualitative confirmation". The need to do so is related to the fact that, without such a conceptualization, a large portion of the human sciences are relegated to a less than scientific status. Accordingly, "qualitative confirmation" is viewed as a proper subset of traditional confirmation theory. To establish such a case, a general Hempelian framework is utilized, but it is supplemented with two additional levels of confirmation. It is concluded that the (...) final test for adequacy of such confirmation must rest on a subjective probability notion. (shrink)

Jean Perrin’s argument for the existence of molecules from his 1908 experimental determination of Avogadro’s number raises two questions considered in this article. One is historical: Why as late as 1908 should Perrin have thought it necessary to argue that molecules exist? The other, which takes up the bulk of this article, is philosophical: In view of the fact that his argument appears to assume the existence of molecules as a premise, how, if at all, can a charge of circularity (...) be avoided? I criticize attempted reconstructions of his argument by Salmon, Glymour, and hypothetico-deductivists. And I propose a probabilistic solution that avoids circularity. Finally, I consider whether Perrin’s reasoning, so construed, is an empirical argument for scientific realism. (shrink)