Alexander James Bird

Thomas Kuhn (1922-96) transformed the philosophy of science. His seminal 1962 work "The Structure of Scientific Revolutions" introduced the term 'paradigm shift' into the vernacular and remains a fundamental text in the study of the history and philosophy of science. This introduction to Kuhn's ideas covers the breadth of his philosophical work, situating "The Structure of Scientific Revolutions" within Kuhn's wider thought and drawing attention to the development of his ideas over time. Kuhn's work is assessed within the context of other philosophies of science notably logical empiricism and recent developments in naturalized epistemology. The author argues that Kuhn's thinking betrays a residual commitment to many theses characteristic of the empiricists he set out to challenge. Kuhn's influence on the history and philosophy of science is assessed and where the field may be heading in the wake of Kuhn's ideas is explored.

In his (2002) Gonzalo Rodriguez-Pereyra provides a powerful articulation of the claim that Resemblance Nominalism provides the best answer to the so-called Problem of Universals. Resemblance Nominalism has not been popular for some time, and one influential reason for this is the widespread belief that Resemblance Nominalism cannot dispense with all universals. The realist critics appeal to what is known as Russell’s Regress (cf. Russell 1997). If properties are to be explained in terms of one object’s resembling another, then this seems to leave the relational property of resemblance itself unexplained. The critics’ objection is that this property itself must be explained by a dyadic universal of resemblance.

Essentialism as applied to individuals is the claim that for at least some individuals there are properties that those individuals possess essentially. What it is to possess a property essentially is a matter of debate. To possess a property essentially is often taken to be akin to possessing a property necessarily, but stronger, although this is not a feature of Aristotle’s essentialism, according to which essential properties are those thing could not lose without ceasing to exist. Kit Fine (1994) takes essential properties to be those that an object has in virtue of its identity, while other essentialists refer (as Fine also does) to the nature of an object as the source of its essential properties. It is sometimes important to distinguish the essential properties of a thing and the ‘full’ essence of a thing. The latter is the set of the essential properties of a thing, when that set necessarily suffices to determine the thing’s identity. One might hold that something has essential properties without agreeing that it has an identity-determining essence. Essentialism was largely in abeyance during the first two thirds of the twentieth century thanks to the domination of analytic philosophy by anti-metaphysical logical empiricism and the linguistic turn. The rehabilitation of essentialism owes much to the development of a formal apparatus for the understanding of modality more generally, thanks to C. I. Lewis, Ruth Barcan Marcus, and Saul Kripke. Kripke’s discussion of essentialism both about individuals and also about about natural kinds brought essentialism to wider philosophical prominence. Natural kind essentialism, which finds its modern genesis also in the work of Hilary Putnam, claims that natural kinds have essential properties: to say that possession of property P is is part of the essence of the kind K implies that, necessarily, every member or sample of the kind K possesses P. Essentialism about individuals has been linked to thinking about natural kinds by the contentious claim that one of the essential properties of any entity is that it belongs to the natural kind (or kinds) it actually belongs to. In this chapter I shall first outline certain claims and arguments concerning essentialism concerning individuals (Section 2)..

In Bird 2001 I argued that a law that might seem to many to be contingent is in fact necessary. In short the argument is this. Given the existence of salt and water, Coulomb’s law of electrostatic attraction is sufficient to make the former dissolve in the latter. So any possible world in which salt failed to dissolve in water would be one in which Coulomb’s law is false. However, it is also the case that the existence of salt depends on Coulomb’s law. If Coulomb’s law is false then salt cannot exist. So there is no possible world in which salt exists and in which it does not dissolve in water.

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.

This paper concerns the relationship between dispositions and ceteris paribus laws. Dispositions are related to conditionals. Typically a fragile glass will break if struck with force. But possession of the disposition does not entail the corresponding simple (subjunctive or counterfactual) conditional. The phenomena of finks and antidotes show that an object may possess the disposition without the conditional being true. Finks and antidotes may be thought of as exceptions to the straightforward relation between disposition and conditional. The existence of these phenomena is easy to demonstrate at the macro-Ievel. But do they exist at the fundamental level also? While fundamental finkish dispositions may be excluded fairly straightforwardly, the existence of fundamental antidotes is more open. Nonetheless I conclude that the phenomenon is likely to be less widespread than at the macro level and that fundamental antidotes may be eliminable. According to the dispositional essentialist, the laws of nature can be explained by taking natural properties to be essentially dispositional. This account can be extended to show that the existence of finks and antidotes explains ceteris paribus laws. Consequently the existence or otherwise of fundamental finks and antidotes sheds some light on the question of whether fundamental laws may also be ceteris paribus laws.

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.

I show that Armstrong’s view of laws as second-order contingent relations of ‘necessitation’ among categorical properties faces a dilemma. The necessitation relation confers a relation of extensional inclusion (‘constant conjunction’) on its relata. It does so either necessarily or contingently. If necessarily, it is not a categorical relation (in the relevant sense). If contingently, then an explanation is required of how it confers extensional inclusion. That explanation will need to appeal to a third-order relation between necessitation and extensional inclusion. The same dilemma reappears at this level. Either Armstrong must concede that some properties are not categorical but have essential powers – or he is faced with a regress.

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.

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.

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.