Online research in philosophy

In the last 30 years repeated attempts have been made to develop a proof-sketch Kripke gave for essentialism about material origins into a cogent argument. I argue that there are general reasons that all such attempts have failed, and so we should likewise expect future attempts to fail.

The article reviews recent developments in England in the law of necessity as a defence to crime and calls for its further extension. It argues that the defence of necessity presents the criminal law with difficult questions of competing values and the ordering of harms. English law has taken a nuanced position on the respective roles of the courts and the legislature in the ordering of harms, although the development of the law has been pragmatic rather than coherently theorised. The law has granted necessity some scope as an exculpatory principle in the law of general defences, but it has also respected the primacy of the legislature as the legitimate arbiter of many of the competitions of value that necessity throws up. The recognition of necessity has not been in the form of a single unified defence of that name. Rather it has taken the form of a number of defences, based on a principle of necessity, but with different nomenclature and different rationales. This approach to necessity is defended as right in terms of principle and policy. Any further development of necessity as a general defence should be restricted to two contexts, namely those of emergencies, and of conflicts of duty, where a danger of death or serious injury is present.

Could a work of art actually authored by one artist have been authored, instead, by another? This is the question of the necessity of authorship. After distinguishing this question from another, regarding individuation, with which it is often confused, this paper offers an argument that authorship is indeed a necessary feature of most artworks. The argument proceeds from ‘independence principles’, which govern the processes by which artworks are produced. Independence principles are motivated, in turn, by metaphysical reflections on what it takes to prevent an artist from producing a particular work of art.

A major source of latter-day skepticism about necessity is the work of David Hume. Hume is widely taken to have endorsed the Humean claim : there are no necessary connections between distinct existences. The Humean claim is defended on the grounds that necessary connections between wholly distinct things would be mysterious and inexplicable. Philosophers deploy this claim in the service of a wide variety of philosophical projects. But Saul Kripke has argued that it is false. According to Kripke, there are necessary connections between distinct existences; in particular, there are necessary connections between material objects and their material origins. This essay argues that the primary motivation for the Humean claim, Hume's datum , also motivates the key premise in an argument for the necessity of origins. The very considerations that the Humean takes to show that necessary connections between wholly distinct things would be mysterious and inexplicable indicate that there must be some such necessary connections. Thus, in the absence of alternative support, there is no reason to believe the Humean claim.

The paper offers an explanation of the intuitive appeal of Saul Kripke's necessity of origin thesis, exhibiting it as the consequence of a temporally asymmetrical 'branching model' of possibilities which, in turn, rests on two plausible principles concerning possibility, time, and identity. Unlike some other accounts, my explanation dissociates the necessity of origin thesis from a commitment to individual essences or other sufficient conditions for identity across possible worlds. I conclude that although the branching model is not irresistible, its rejection may necessitate the denial of a plausible principle that requires possibilities for actual individuals to be 'anchored' to their actual characteristics.

In the last 30 years much philosophical discussion has been generated by Kripke’s proof of the necessity of origin for material objects presented in footnote 56 of ‘Naming and Necessity’. I consider the two most popular reconstructions of Kripke’s argument: one appealing to the necessary sufficiency of origin, and the other employing a strong independence principle allegedly derived from the necessary local nature of prevention. I argue that, to achieve a general result, both reconstructions presuppose an implicit Humean atomistic thesis of recombination, according to which any two (non-overlapping) possible objects can simultaneously coexist in one and the same world. Yet recombination ill accords with the other assumptions of the proofs. I also argue that the locality of prevention does not entail strong independence.

In a famous footnote in Naming and Necessity, Kripke offered “something like a proof” of the thesis that material things have their material origins essentially (EMO). Although the sketch of a proof Kripke gave was incomplete in important respects, many philosophers have since endeavoured to develop Kripke’s style of argument so that it reaches its intended conclusion.1 In particular, a number of philosophers have attempted to complete Kripke’s argument sketch by appealing to some sort of “sufficiency principle” – a principle that gives sufficient conditions for the identity of objects across possible worlds. These developments of Kripke’s argument face a number of problems, as pointed out by Mackie (1987, 2002), Robertson (1998, 2000) and others.2 Recently, however, Rohrbaugh and deRosset (2004, 2006) have offered a new route to origin essentialism that develops a Kripke-style argument without appeal to a sufficiency principle. While this argument has also not escaped criticism3, the argument suffers from a crucial flaw which has not been noticed. More interesting, though, is that the problem the argument faces is the same problem facing the arguments that appeal to sufficiency principles, and indeed Kripke’s original “proof” – all these arguments over-generalize. This strongly suggests that there is no Kripkestyle route to origin essentialism.

A New Route to the Necessity of Origin’, Guy Rohrbaugh and Louis deRossett argue for the Necessity of Origin in a way that they believe avoids use of any kind of transworld constitutional sufficiency principle. In this discussion, we respond that either their arguments do imply a sufficiency principle, or else they entirely fail to establish the Necessity of Origin.

A New Route to the Necessity of Origin’ (2004, henceforth ‘NR’), we offered an argument for the thesis that there are necessary connections between material things and their material origins. Much of the philosophical interest lay in our claim that the argument did not depend on so-called sufficiency principles for crossworld identity. It has been the verdict of much recent work on the necessity of origin that valid arguments for the thesis require some such sufficiency principle as a premise but that such principles are deeply problematic.1 Finding an argument free of such principles would advance both our understanding and the plausibility of that thesis. These claims are now the subject of a pair of insightful critiques by Teresa Robertson and Graeme Forbes (2006, henceforth ‘RF’) and by Ross Cameron and Sonia Roca (2006, henceforth ‘CR’), and we welcome the opportunity to clarify and improve our account of the matter.

In ‘A New Route to the Necessity of Origin’, Rohbraugh and deRosset offer an argument for the Necessity of Origin appealing neither to Suffciency of Origin nor to a branching-times model of necessity. What is doing the crucial work in their argument is instead the thesis they name ‘Locality of Prevention’. In this response, we object that their argument is question-begging by showing, first, that the locality of prevention thesis is not strong enough to satisfactorily derive from it the intended conclusion, and, second, that the argument is not sound unless the Necessity of Origin is operating as an implicit premiss.