I've been thinking about essence some more (what with essentialism being the focus of my thesis I can imagine a lot of my posts starting this way). Specifically I've been thinking about the new breed of essentialism, and how the thinkers involved think about it. I've read a fair bit of the new literature on essence (the stuff post 1994 when Fine argued against the modal understanding of essence) and related notions, and I'm still rather confused as to just how I should formulate the main essentialist claim. The thinkers I have in mind are folk like Fine, Lowe, Correia, and Shalkowski. I've also discussed the topic with the last two but and with others like Dasgupta, and Divers (and grad students, notably Michael Bench-Capon and Thomas Brouwer). The overwhelming impression I get from all this is that, whilst there is clearly some notion of essence that unifies all these people, it is by no means clear exactly how it should be exactly interpreted. What is clear is how one might interpret essence in broad strokes. On the 'new generation' conception of essence it is not necessity de re, but what it is for things to be the things that they are. I describe this as an ontological interpretation as opposed to a modal one, as whatever essence is, it is linked closely with the identities of things. However, once we accept this (rather vague) idea, it becomes quite tricky to agree on just about anything else, be it the nature of essence, or its role in modern metaphysics.
Issues people can differ on include a bunch of tricky topics, but today I'm going to talk about the direction of explanation. The question comes from two different and (seemingly) equally plausible ways that one might phrase a general essentialist claim. The first claims that 'the essence of x is that in virtue of which x is the individual that it is'. Alternatively one might say 'the essence of x is that which follows from what x is (in adherence with the tradition that italics make phrases more meaningful). The end of this one can be rephrased as 'from x's identity', or even x's 'metaphysical identity' (apply italics to taste)'. Both of these sound like pretty good ways of summing up what essence is, and both have precedents in the literature. The problem is that each points the explanation in the opposite direction from the other. In the first case it is the essence of x that makes it what it is. The second makes x's essence something that follows from what x is.
The former seems to be more in keeping with our intuitions, right? I mean, if essence is to play a useful role in your metaphysics, it should be 'making you the thing that you are', or 'grounding your identity', or whatever. Chaps like Lowe and Shalkowski seem more inclined this way (looks that way to me anyway, especially when you think about what Lowe wants essence to do for modal epistemology). But it looks like folk like Fine and Dasgupta favour the latter option. At least, this is how it looks when you think about Fine's stuff on real definition. This claims that the essence of x is the real definition of x (Fine only offers this as a heuristic, but sometimes I wonder why he doesn't try to do more... More on that when I'm less confused). A real definition is supposed to be a metaphysical analogue to the way that we give nominal definitions of terms. Fine identities the real definition of x with the collection of propositions that are true in virtue of its identity (or with the corresponding collection of essential properties).
A nice, easy way of seeing why this difference is significant is in the kinds of traditional essential predications that these interpretations support. For instance, the former favours essential origins whilst the latter does not, and the latter favours essentially having such and such persistence conditions where it doesn't seem obvious (at least to me) that the former does. Here's why I think this. If we think of in virtue of (oh boy, here he goes with the italics again) as being grounds, then it seems pretty safe to think that x's identity is (at least in part) grounded in x's origins. Conversely, to say that x having certain origins is grounded in x's identity is, well it's weird. Likewise, it looks pretty safe to say that x's persistence conditions could be grounded in x's identity, but it looks less appetising to think the other way around (though I suppose it's not that weird... Oh will you quit with the italics already!).
It looks to me like one of several things might be going on. Maybe I'm misinterpreting what Fine means by 'in virtue of'. Maybe it is supposed to be more to do with what you can infer, in which case I can much more confidently infer the importance of x's origins from it's identity. Maybe Fine just doesn't want essence to do what I'm thinking of, after all, it looks like his way makes essence a better candidate for providing the grounds to modal facts. Maybe I've drank too much tea this year and I'm going loopy. But maybe, just maybe I'm actually worried about something legitimate and this is a real problem for the essentialist camp. After all, even if you follow Fine to the letter there is still something uncomfortable about reconciling the notion of essences as real definitions with Fine's desired direction of explanation. Is that how we think of nominal definitions? No, we think of them as telling us what a term means, not telling us what it true in virtue of the meaning of the term (Oi!). Even if my intuitions are faulty on this one (perfectly possible for someone who attributes italics semantic content but refuses to specify what that content is), but even so, there appears to be a lack of unity in this generation of essentialists, even when it comes to the most basic aspects of the nature of essence.
The problem gets even worse when you bring stuff like ontological dependence into the picture. Maybe I'll talk about that next time, if I've had enough tea.