Traditionally, metaphysical claims - e.g. answers to the special composition question, theories of properties - are taken to be necessary if true, while general claims about the natural world - laws of nature, or laws of emergence, if there are any - are taken to be contingent. For a few years, necessitarianian heretics have questioned the contingency of general claims about the natural world. Even more recently, contingentist heretics have questioned the non-contingency of metaphysical claims. Both ensuing debates have brought various issues in the metaphysics and the epistemology of modality into sharper focus. The aim of the workshop is to pursue them further, and to link up the two debates.
The aim of the workshop is to link up the current debate about metaphysical contingentism (about properties, composition, analyticity etc.) with the older debate on modal contingentism, denying the Brouwersche axiom or S4 for metaphysical modality.
This workshop is part of the sinergia project "Intentionality - the Mark of the Mental. Metaphysical Perspectives on Contemporary Philosophy of Mind", of the SNSF graduate school "Contemporary issues on ontological commitment: fictionalism and fundamentality" (101111-130363), and of the philosophy doctoral programme of the CUSO.
The conference starts on the 24th and ends on the 25th of September 2010 (evening).
Friday, 24th of September:
Orthodoxy has it that metaphysical claims are non-contingent. Recently, this necessitarian orthodoxy has been challenged by so-called "metaphysical contingentists". They pointed out that necessitarianism is supported by little more than prejudice. But in my view, extant work on contingentism does not give us much positive reason to believe in the contingency of metaphysical claims, rather than remain agnostic about the matter. I suggest that metaphysical contingentism ought to be defended as part of an attractive general theory of what is possible and what is impossible. An important constraint on such a theory is that it draws the line between the possible and the impossible in a non-arbitrary fashion. A theory according to which it is possible that there is a fifteen meter high unicycle, and also possible that there is a seventeen meter high unicycle, but impossible that there is a sixteen meter high unicycle would not satisfy that constraint.
The claim that there are no brute necessities is a general theory that entails metaphysical contingentism (unless it is combined with a very restrictive view of when a necessity is brute). It can be captured by the following thesis:
CP: For all propositions p, if p is conceivable, then p is possible.
The theory articulated by CP does seem to satisfy the non-arbitrariness constraint. But is the theory defensible? Many philosophers have thought not. If they are right, we seem to be back at a stalemate between necessitarianism and contingentism. In previous talks in Geneva, I discussed a number of objections to this view. In this talk, I want to discuss a new one, which arises from features of the notion of conceivability with the help of which the theory is stated.
The notion of conceivability which I deploy in CP is roughly what Chalmers calls "ideal negative conceivability": p is conceivable iff its negation is not (ideally) demonstrable. That is, conceivability is the dual of demonstrability. (However, I do not buy into Chalmers "primary"/"secondary" distinction, nor into his rationalist, expansive view of what is demonstrable, which prevents him from being a metaphysical contingentist.) I will also use "coherent" instead of "conceivable".
The objection to CP turns on failures of E, the characteristic axiom of S5-logic, for demonstrability and its dual coherence:
E: If p is coherent, then p is demonstrably coherent.
According to the standard view, E fails in demonstrability logic. But if p is a false instance of E, then with CP, we can derive that p is coherent but possibly incoherent. Coherence (or conceivability) itself becomes a contingent matter! The idea that metaphysically possible worlds differ with respect to what is coherent in them is very hard to make sense of, even for a committed contingentist. In the talk, I will discuss different response strategies for a defender of CP.
Saturday, 25th of September
I examine the peculiar and ill-understood notion of metaphysical explanation / analysis / account and argue that it can hold contingently: not only may the explanans be contingently true, but the explanatory relation between (the entities concerned by) it and (the entities concerned by) the explanandum may hold contingently. I distinguish this case from the quite different one where the explanation is only partial and give particular attention to the in my view paradigmatic case of explanation by things, arguing that it, too, may hold only contingently.
both days, we'll meet in the seminar room L208, on the 2nd floor of 4,
rue de Candolle -- that's where the department is on the 4th floor.