Tom Stoneham

We argue that genuine modal realism can be extended, rather than modified, so as to allow for the possibility of nothing concrete, a possibility we term ‘metaphysical nihilism’. The issue should be important to the genuine modal realist because, not only is metaphysical nihilism itself intuitively plausible, but also it is supported by an argument with pre-theoretically credible premises, namely, the subtraction argument. Given the soundness of the subtraction argument, we show that there are two ways that the genuine modal realist can accommodate metaphysical nihilism: (i) by allowing for worlds containing only spatiotemporal points and (ii) by allowing for a world containing nothing but the null individual. On methodological grounds, we argue that the genuine modal realist should reject the former way but embrace the latter way.

Suppose nothing exists. Then it is true that nothing exists. What makes that true? Nothing! So it seems that if nothing existed, then the principle that every truth is made true by something (the truthmaker principle) would be false. So if it is possible that nothing exists, a claim often called 'metaphysical nihilism', then the truthmaker principle is not necessary. This paper explores various ways to resolve this conflict without restricting metaphysical nihilism in such a way that it would become trivial and uninteresting.

Paul Boghossian has argued that Externalism is incompatible with privileged self-knowledge because (i) the Externalist can cite no property to be the reference of an empty natural kind concept such as the ether; (ii) without reference there is no content; hence (iii) either we do know on the basis of introspection alone whether an apparent natural kind thought has content or not, in which case we can infer from self-knowledge and a priori knowledge of Externalism alone to the existence in our environment of water, gold etc.; (iv) or we do not know, without empirical investigation, whether an apparent natural kind thought has content. An Externalist not wanting to accept either (iii) or (iv) can deny (i). All empty natural kind concepts refer to the necessarily uninstantiated property of being identical to nothing. Since they have different senses and self-knowledge is only held to extend to the existence and identity of sense, this is compatible with privileged self-knowledge, and Externalism is still true of the concepts