Alexander James Bird

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.

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.

Peter Lipton argues that inference to the best explanation involves the selection of a hypothesis on the basis of its loveliness. I argue that in optimal cases of IBE we may be able to eliminate all but one of the hypotheses. In such cases we have a form of eliminative induction takes place, which I call ‘Holmesian inference’. I argue that Lipton’s example in which Ignaz Semmelweis identified a cause of puerperal fever better illustrates Holmesian inference than Liptonian IBE. I consider in detail the conditions under which Holmesian inference is possible and conclude by considering the epistemological relations between Holmesian inference and Liptonian IBE.Keywords: Inference to the best explanation; Peter Lipton; Abduction; Holmesian inference; Eliminative induction.

Natural kind terms appear to behave like singular terms. If they were genuine singular terms, appearing in true sentences, that would be some reason to believe that there are entities to which the terms refer, the natural kinds. Paul Needham has attacked my arguments that natural kind terms are singular, referring expressions. While conceding the correctness of some of his criticisms, I defend and expand on the underlying view in this paper. I also briefly sketch an account of what natural kinds in fact are—natural complexes of sparse (natural) universals.

Why, despite his enormous influence in the latter part of the twentieth century, has Kuhn left no distinctively Kuhnian legacy? I argue that this is because the development of Kuhn’s own thought was in a direction opposite to that of the mainstream of the philosophy of science. In the 1970s and 1980s the philosophy of science took on board the lessons of externalism as regards reference and knowledge, and became more sympathetic to a naturalistic approach to philosophical problems. Kuhn, on the other hand, started out with a strong naturalistic streak, employing non-philosophical disciplines, primarily psychology, in order to build his accounts of scientific change and the nature of observation and scientific thought. But by the 1970s Kuhn’s work had taken on a much more purely philosophical, a priori, tone. His explanation of incommensurability moved from a psychological explanation to one embedded in the philosophy of language. Increasingly he gave his outlook a Kantian gloss. I suggest, nonetheless, that Kuhn’s most valuable contribution is to be found in The Structure of Scientific Revolutions and not in his later work, and that the naturalistic direction of the former has important links with connectionist research in cognitive science that deserve further study.Author Keywords: Kuhn; Scientific revolutions; Empiricism; Naturalism; Incommensurability; Reference.

Arguing About Science is an outstanding, engaging introduction to the essential topics in philosophy of science, edited by two leading experts in the field. This exciting and innovative anthology contains a selection of classic and contemporary readings that examine a broad range of issues, from classic problems such as scientific reasoning; causation; and scientific realism, to more recent topics such as science and race; forensic science; and the scientific status of medicine. The editors bring together some of the most influential contributions of famous philosophers in the field, including John Stuart Mill and Karl Popper, as well as more recent extracts from philosophers and scientists such as Ian Hacking, Stephen Jay Gould, Bas van Fraassen, Nancy Cartwright, and John Worrall. The anthology is organised into nine clear sections: science, non science and pseudo-science race, gender and science scientific reasoning scientific explanation laws and causation science and medicine probability and forensic science risk, uncertainty and science policy scientific realism and anti-realism. The articles chosen are clear, interesting, and free from unnecessary jargon. The editors provide lucid introductions to each section in which they provide an overview of the debate, as well as suggestions for further reading.

Dispositional monism is the view that natural properties and relations are ‘pure powers’. It is objected that dispositional monism involves some kind of vicious or otherwise unpalatable regress or circularity. I examine ways of making this objection precise. The most pressing interpretation is that is fails to make the identities of powers determinate. I demonstrate that this objection is in error. It does however puts certain constraints on what the structure of fundamental properties is like. I show what a satisfactory structure would be.

In 'Necessarily, salt dissolves in water' (Analysis 61 (2001)), I argued that because the laws required for the existence of salt entail the laws that ensure dissolving in water, there is no possible world in which salt exists but fails to dissolve in water. In this paper I respond to criticisms from Helen Beebee and Stathis Psillos (Analysis 62 (2002)). I also introduce the 'down-and-up' structure, generalising the case. Whether or not this structure is instantiated is a matter for a posteriori discovery. Hence not only are some laws necessary (but known a posteriori), but furthermore whether a given law is necessary or contingent will also be a matter of a posteriori discovery.

Thomas Samuel Kuhn (1922–1996) is one of the most influential philosophers of science of the twentieth century, perhaps the most influential. His 1962 book The Structure of Scientific Revolutions is one of the most cited academic books of all time. Kuhn’s contribution to the philosophy of science marked not only a break with several key positivist doctrines, but also inaugurated a new style of philosophy of science that brought it closer to the history of science. His account of the development of science held that science enjoys periods of stable growth punctuated by revisionary revolutions. To this thesis, Kuhn added the controversial ‘incommensurability thesis’, that theories from differing periods suffer from certain deep kinds of failure of comparability.

In my 'Dispositions and Antidotes', The Philosophical Quarterly, 48 (1998), I raise an objection to the conditional analysis of dispositions, both in its simple formulation and in a more sophisticated version due to David Lewis, The Philosophical Quarterly, 47 (1997). The objection suggests that a disposition may be continuously present and the appropriate stimulus occur without the manifestation occurring, because some outside influence, an antidote, interferes. Gundersen in The Philosophical Quarterly, 50 (2000), argues that my objection rests on an equivocation about which object possesses the disposition and more particularly on an equivocation about the context in which the events referred to take place, and that when the equivocation is resolved the counter-example disappears. I respond by showing that the counter-example does remain if we take contextual and mereological issues into account, and I conclude by remarking that the difference with Lewisdepends on whether certain features are seen as significant for the semanticsand metaphysics of dispositions or as merely characteristic of the pragmaticsof common usage.

1.Following Kripke, many philosophers have accepted the existence of propositions concerning essences, and, more generally, propositions asserting necessities, that are knowable only a posteriori. Such an acceptance is consistent with the claim that ultimately all knowledge of necessity is a priori. A posteriori knowledge of necessity may be held to be a consequence of the combination of a priori knowledge of a proposition asserting essence or necessity with a posteriori knowledge of a non-modal proposition. E. J. Lowe (2007: 287–88) denies even this kind of derived a posteriori knowledge of essence or necessity. He reconstructs the form of an argument that is intended to lead to a proposition concerning essence but which is known a posteriori: This schema may be exemplified thus: As this example illustrates, instances of (1) are a priori propositions concerning essence, while instances of (2) are a posteriori propositions; instances of the conclusion are propositions asserting particular essences, and are, it is claimed, knowable only a posteriori.1.

We talk as if there are natural kinds and in particular we quantify over them. We can count the number of elements discovered by Sir Humphrey Davy, or the number of kinds of particle in the standard model. Consequently, it looks at first sight at least, that natural kinds are entities of a sort. In the light of this we may ask certain questions: is the apparent existence of natural kinds real or an illusion? And if real, what sort of entity are natural kinds? Are they sui generis? Or can they be identified with or reduced to some other kind of entity? In this essay I shall look at possible reasons for asserting that either kinds are no sort of entity, or, if they are entities, their existence is equivalent to some fact not involving kinds. Richard Boyd seems to take the view that the apparent existence of natural kinds is an illusion.

I defend against criticism the following claims concening Thomas Kuhn: (i) there is a strong naturalist streak in The structure of scientific revolutions, whereby Kuhn used the results of a posteriori enquiry in addressing philosophical questions; (ii) as Kuhn's career as a philosopher of science developed he tended to drop the naturalistic elements and to replace them with more traditionally philosophical a prior approaches; (iii) at the same there is a significant residue of positivist thought in Kuhm, which Kuhn did not recognise as such; (iv) the naturalist elements referred to in (i) are the most original and fruitful elements of Kuhn's thinking; (v) the positivistic elements referred to in (iii) vitiated his thought and acted as factors in preventing Kuhn from developing the naturalistic elemtns and from following the path taken by much subsequent philosophy of science. Preston presents an alternative reading of Kuhn which emphasizes the Wittgensteinian elements in Kuhn. I argue that this alternative view is, descriptively, poorly supported by the textual evidence and the facts of the history of philosophy of science in the twentieth century. I provide some defence of the naturalistic approach and related themes.