I’ve now got a draft of my paper for the Meaning, Modality and Apriority symposium with Scott Soames. You can get it from here. The abstract of the talk is here. The paper does pretty much what I promise in the abstract: I first summarise Soames’ account of the necessary a posteriori, then I look into Alan Sidelle’s deflationary account of it, and attempt to demonstrate that these two accounts are remarkably close to each other. Hence, Soames is at a risk of sliding towards the view according to which modality is linguistic and the a priori reduces to analyticity — which is a view that he strongly opposes.

I then go on to give an analysis of what I believe is missing both from Soames’ and Sidelle’s account: an examination of the a priori, essentialist principles which are responsible for the modal content of the necessary a posteriori. Since the main example being discussed is that of water, I look into some recent work in the philosophy of chemistry, especially by Robin Hendry. I argue that we will need a detailed analysis of the nature of chemical substances, and specifically whether chemical substances have their molecular structures essentially to determine whether ‘Water is H20′ is an example of the necessary a posteriori. Hendry’s analysis of the case is a good example of how I think the essentialist account should proceed.

The upshot is that Soames is at a crossroads: either he should concede to the deflationist and adopt the view that modality is linguistic and the a priori can be identified with the analytic, or he should engage in the type of work that we saw in Hendry’s suggestion: a detailed analysis of the underlying essentialist principles. Given that Soames is one of the loudest critics of the deflationary approach, I would hope that he is more tempted by the latter option.

The paper is still in draft stage, so comments are especially welcome. I will present the paper in Cologne on May 19th.