Alexander James Bird

Those who favour an ontology based on dispositions are thereby able to provide a dispositional essentialist account of the laws of nature. In part 1 of this paper I sketch the dispositional essentialist conception of properties and the concomitant account of laws. In part 2, I characterise various claims about the modal character of properties that fall under the heading ‘quidditism’ and which are consequences of the categoricalist view of properties, which is the alternative to the dispositional essentialist view. I argue that quidditism should be rejected. In part 3, I address a criticism of a strong dispositional essentialist view, viz. that ‘structural’ (i.e. geometrical, numerical, spatial and temporal) properties must be regarded as categorical.

Selection explanations explain some non-accidental generalizations in virtue of a selection process. Such explanations are not particulaizable - they do not transfer as explanations of the instances of such generalizations. This is unlike many explanations in the physical sciences, where the explanation of the general fact also provides an explanation of its instances (i.e. standard D-N explanations). Are selection explanations (e.g. in biology) therefore a different kind of explanation? I argue that to understand this issue, we need to see that a standard D-N explanation of some non-accidental generalization (al Fs are Gs) may also ipso facto explain its contrapositive (all non-Gs are non-Fs), but the explanation is particularizable with respect to the former but not to the latter. This can be seen by noting that the Raven Paradox counterexample to the H-D model of confirmation also generates a counterexample to the D-N model of explanation (all ravens are black does not explain why the non-black shoe is a non-raven). In such cases it is natural to take the generalization with the positive predicates to have a particularizable explanation. However, this need not be the case, and in selection explanations it is the generalization with the positive predicates whose explanation is no particularizable. Thus there is no need to suppose that selection explanations are fundamentally different.

The usual, comparative, conception of inference to the best explanation (IBE) takes it to be ampliative. In this paper I propose a conception of IBE ('Holmesian inference') that takes it to be a species of eliminative induction and hence not ampliative. This avoids several problems for comparative IBE (for example, how could it be reliable enough to generate knowledge?). My account of Holmesian inference raises the suspicion that it could never be applied, on the grounds that scientific hypotheses are inevitably underdetermined by the evidence (i.e. are inevitably ampliative). I argue that this concern may be resisted by acknowledging, as Timothy Williamson has shown, that all knowledge is evidence. The latter suggests an approach to resisting scepticism different from those (e.g. the reliabilist approach) that embrace fallibilism.

In this paper I draw a connection between Kuhn and the empiricist legacy, specifically between his thesis of incommensurability, in particular in its later taxonomic form, and van Fraassen's constructive empiricism. I show that if it is the case the empirically equivalent but genuinely distinct theories do exist, then we can expect such theories to be taxonomically incommensurable. I link this to Hacking's claim that Kuhn was a nominalist. I also argue that Kuhn and van Fraassen do not differ as much as might be thought as regards the claim that observation is theory laden.

Frege's logicism consists of two theses: the truths of arithmetic are truths of logic; the natural numbers are objects. In this paper I pose the question: what conception of logic is required to defend these theses? I hold that there exists an appropriate and natural conception of logic in virtue of which Hume's principle is a logical truth. Hume's principle, which states that the number of Fs is the number of Gs iff the concepts F and G are equinumerous is the central plank in the neo-logicist argument for and. I defend this position against two objections Hume's principle canot be both a logical truth as required by and also have the ontological import required by ; and the use of Hume's principle by the logicist is in effect an ontological proof of a kind which is not valid

Many introductions to this field start with the problem of justifying scientific knowledge but Alexander Bird begins by examining the subject matter, or metaphysics, of science. Using topical scientific debates he vividly elucidates what it is for the world to be governed by laws of nature. This idea provides the basis for explanations and causes and leads to a discussion of natural kinds and theoretical entities. With this foundation in place he goes on to consider the epistemological issues of how science arrives at knowledge, favouring a treatment of scientific reasoning based on inference to the best explanation. Drawing on contemporary work in epistemology, Bird argues that scepticism about induction should not be a problem for science and examines the consequences of this position for controversies surrounding the ideas of scientific progress and scientific revolution. Bird's insightful treatment makes Philosophy of Science an ideal text for undergraduate courses. The guides to further reading provided in each chapter help the reader pursue interesting topics and facilitate the use of the book in conjunction with primary sources

This paper sketches a dispositionalist conception of laws and shows how the dispositionalist should respond to certain objections. The view that properties are essentially dispositional is able to provide an account of laws that avoids the problems that face the two views of laws (the regularity and the contingent nomic necessitation views) that regard properties as categorical and laws as contingent. I discuss and reject the objections that (i) this view makes laws necessary whereas they are contingent; (ii) this view cannot account for certain kinds of laws of nature and their properties.

In this paper I aim to show that a certain law of nature, namely that common salt (sodium chloride) dissolves in water, is metaphysically necessary. The importance of this result is that it conflicts with a widely shared intuition that the laws of nature (most if not all) are contingent. There have been debates over whether some laws, such as Newton’s second law, might be definitional of their key terms and hence necessary. But the law that salt dissolves in water is not that kind of law. The law statement ‘salt dissolves in water’ is clearly synthetic. It appears a classic case of a contingent law. We like to believe that there are possible worlds in which the laws of nature are different and in which salt does not dissolve in water.