We discuss from a philosophical perspective the way in which the normal concept of time might be said to `emerge' in a quantum theory of gravity. After an introduction, we briefly discuss the notion of emergence, without regard to time. We then introduce the search for a quantum theory of gravity ; and review some general interpretative issues about space, time and matter. We then discuss the emergence of time in simple quantum geometrodynamics, and in the Euclidean approach. Section 6 (...) concludes. (shrink)

In his new foreword to this edition, Hilary Putnam forcefully rejects these nativist claims.

Counterfactuals is David Lewis' forceful presentation of and sustained argument for a particular view about propositions which express contrary to fact conditionals, including his famous defense of realism about possible worlds and his theory of laws of nature.

These nine essays address fundamental questions about time in philosophy, physics, linguistics, and psychology. Are there facts about the future? Could we affect the past? In physics, general relativity and quantum theory give contradictory treatments of time. So in the current search for a theory of quantum gravity, which should give way: general relativity or quantum theory? In linguistics and psychology, how does our language represent time, and how do our minds keep track of it?

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. (shrink)

1. Contextualism seeks to acknowledge the power of sceptical arguments while permitting to be true at least some of the assertions of knowledge and justification we commonly make. It seems to me now just as if I am in an office in Edinburgh. According to the sceptic the claim that I am in fact in an office in Edinburgh is unjustified, since there is no reason I can give for this belief that is not also consistent with (or undermined by) (...) the alternative hypothesis that I am in fact on a beach in Hawaii being deceived by an evil demon into thinking that I am in an office in Edinburgh. Yet if I were.. (shrink)

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. (shrink)

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. (shrink)

In a recent paper (Bird 2001), Alexander Bird argues that the law that common salt dissolves in water is metaphysically necessary - and he does so without presupposing dispositionalism about properties. If his argument were sound, it would thus show that at least one law of nature is meta- physically necessary, and it would do so without illicitly presupposing a position (dispositionalism) that is already committed to a necessitarian view of laws. I shall argue that Bird's argument is unsuccesful.

Scientific Essentialism defends the view that the fundamental laws of nature depend on the essential properties of the things on which they are said to operate, and are therefore not independent of them. These laws are not imposed upon the world by God, the forces of nature or anything else, but rather are immanent in the world. Ellis argues that ours is a dynamic world consisting of more or less transient objects which are constantly interacting with each other, and whose (...) identities depend on their roles in these processes. Natural objects must behave as they do, because to do otherwise would be contrary to their natures. The laws of nature are, therefore, metaphysically necessary, and consequently, there are necessary connections between events. Brian Ellis calls for the rejection of the theory of Humean Supervenience and an implementation of a new kind of realism in philosophical analysis. (shrink)