Online research in philosophy

Why should science be so interested in discovering whether p is a law over and above whether p is true? The answer may involve the laws' relation to counterfactuals: p is a law iff p would still have obtained under any counterfactual supposition that is consistent with the laws. But unless we already understand why science is especially concerned with the laws, we cannot explain why science is especially interested in what would have happened under those counterfactual suppositions consistent with the laws. It is argued that the laws form the only non-trivially "stable" set, where "stability" is invariance under a certain range of counterfactual suppositions not itself defined by reference to the laws. It is then explained why science should be so interested in identifying a non-trivially "stable" set: because of stability's relation to the best set of "inductive strategies".

Laws form counterfactually stable sets -- Natural necessity -- Three payoffs of my account -- A world of subjunctives.

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.

Ceteris Paribus (cp-)laws may be said to hold only “other things equal,” signaling that their truth is compatible with a range of exceptions. This paper provides a new semantic account for some of the sentences used to state cp-laws. Its core approach is to relate these laws to natural language on the one hand — by arguing that cp-laws are most naturally expressed with generics — and to natural kinds on the other — by arguing that the semantics of generics in the context of the special sciences are best spelled out by appeal to natural kinds. The paper then goes on to draw on these semantics in order to illuminate several problems raised by cp-laws, some familiar, some new.

I identify the special sort of stability (invariance, resilience, etc.) that distinguishes laws from accidental truths. Although an accident can have a certain invariance under counterfactual suppositions, there is no continuum between laws and accidents here; a law's invariance is different in kind, not in degree, from an accident's. (In particular, a law's range of invariance is not "broader"--at least in the most straightforward sense.) The stability distinctive of the laws is used to explicate what it would mean for there to be multiple grades (or degrees) of physical necessity. Whether there are is for science to discover.

It is often presumed that the laws of nature have special significance for scientific reasoning. But the laws' distinctive roles have proven notoriously difficult to identify--leading some philosophers to question if they hold such roles at all. This study offers original accounts of the roles that natural laws play in connection with counterfactual conditionals, inductive projections, and scientific explanations, and of what the laws must be in order for them to be capable of playing these roles. Particular attention is given to laws of special sciences, levels of scientific explanation, natural kinds, ceteris-paribus clauses, and physically necessary non-laws.

Scientific essentialism aims to account for the natural laws' special capacity to support counterfactuals. I argue that scientific essentialism can do so only by resorting to devices that are just as ad hoc as those that essentialists accuse Humean regularity theories of employing. I conclude by offering an account of the laws' distinctive relation to counterfactuals that portrays laws as contingent but nevertheless distinct from accidents by virtue of possessing a genuine variety of necessity.

In Lange 2004a, I argued that 'scientific essentialism' [Ellis 2001 cannot account for the characteristic relation between laws and counterfactuals without undergoing considerable ad hoc tinkering. In recent papers, Brian Ellis 2005 and Toby Handfield 2005 have defended essentialism against my charge. Here I argue that Ellis's and Handfield's replies fail. Even in ordinary counterfactual reasoning, the 'closest possible world' where the electron's electric charge is 5% greater may have less overlap with the actual world in its fundamental natural kinds than a 'more distant possible world' where the electron's charge is 5% greater. But more importantly, essentialism's flexibility in being able to accommodate virtually any relation between laws and counterfactuals is a symptom of essentialism's explanatory impotence as far as that relation is concerned.

Marc Lange objects to scientific essentialists that they can give no better account of the counterfactual invariance of laws than Humeans. While conceding this point succeeds ad hominem against some essentialists, I show that it does not undermine essentialism in general. Moreover, Lange's alternative account of the relation between laws and counterfactuals is - with minor modification - compatible with essentialism.