## Saturday, 9 December 2017

### Sticking Up for 'Essence = Necessity + Intrinsicality' in the Face of Zylstra's Argument

UPDATE 11/12/2017: The more I think about Zylstra's argument, the more I think I've been overly critical, and not sufficiently open to changing my views. I have moderated some of the worst excesses by editing the below a little bit. I continue to think about the lessons which we should draw from Zylstra's argument, and may come back to the matter in a future post. One thing which has just begun to bother me is that, if we try to take the lesson to show that we'd better make intrinsicality term-relative when it comes to relations, is that the stuff which comes to mind when trying to explicate the resulting notion of "intrinsicality" - I found myself thinking things like 'x bears R to y intrinsically if part of what it is to be x is to be R-related to y' - just ends up sounding like a characterisation of essence; the necessity-ish bit seems to come of its own accord. So maybe there are grounds here for serious doubt about the overall E = N + I approach to essence.

An interesting new paper by Justin Zylstra attempts to cast doubt on the project of analyzing essence in terms of necessity plus something else. As Fine famously pointed out, it is plausible that the set {Soctrates} essentially contains Socrates but that Socrates does not essentially belong to {Socrates}. Being a member of that set does not have enough to do with Socrates as he is in himself, we might say, to count as an essential property of Socrates. Nevertheless, Socrates necessarily belongs to {Socrates}; in no possible world do we find Socrates but not the set containing him.

So essential properties aren't just the necessarily-possessed properties, or so it seems. Fine makes the further proposal that we give up trying to analyze essence in terms of necessity and instead go the other way around. But others have accepted that the essential properties aren't just the necessarily-possessed ones, but sought to supplement the analysis of essence in terms of necessity. I am sympathetic to this approach, and particularly to the idea - prominently defended by Denby - that essence = necessity + intrinsicality. Let's call this the E = N + I approach.

(Denby, it is important to note, favours an account of intrinsicality on which the property of containing Soctrates is not intrinsic, but extrinsic, to {Socrates}. This leads him to push back against the prima facie plausible Finean thesis that containing Socrates is essential to {Socrates}. In my view, this was a mistake on Denby's part, and we should instead try to understand 'intrinsic' in such a way that it does come out true that the property of containing Socrates is intrinsic to {Socrates}.)

You can imagine my interest in Zylstra's paper, which is supposed to cast serious doubt on this approach. Here I want to explain why I think it does no such thing. I won't reconstruct Zylstra's detailed and technically sophisticated argument in full. To fully assess what I'm saying, in particular to verify that I speak the truth about what Zylstra does in his paper, you'd have to look at the paper.

To understand why Zylstra's argument goes as wrong as I think it does, it helps to note that he aims his criticisms more generally at any attempt to supplement a necessity-based analysis of essence so that it delivers the goods on Fine's celebrated examples, provided it is of a certain general form. He intends this form to cover the E = N + I approach. The trouble is, it is very easy to formulate a version of that approach which does not take general form in question.

The central problem with Zylstra's handling of the E = N + I approach is that he considers only Denby's version, which proceeds as if the relevant notion of intrinsicality can be treated as a sentential operator. It is intrinsic that p. But no friend of the E = N + I approach should want to do that.

The whole point of bringing in intrinsicality, I would have thought, is that it is plausibly intrinsic to {Socrates} that it contains Socrates, but not intrinsic to Socrates that he is contained by {Socrates}. But if we represent our idea of intrinsicality as a sentential operator, all we can say is:

It is intrinsic that Socrates is a member of {Socrates}.

or

It is intrinsic that {Socrates} contains Socrates.

or whatever.

Now, this doesn't really even make sense without explanation, but putting that aside, and assuming that such claims will either be true or be false, Zylstra is able to show that an analysis of essence in terms of necessity and this weird intrinsicality sentential operator can't deliver the goods.

But so what? This just shows that the relevant notion of intrinsicality can't be captured as a sentential operator! Indeed, in his last section, entitled 'A glimmer of hope', Zylstra suggests that instead of supplementing a necessity-based analysis of essence with a notion that can be expressed as a sentential operator, we might be able to use an operator that takes a sentence and a noun phrase and produces a sentence:
Recall that the Supplemented Necessity Analysis involved an existentially bound variable O that functions syntactically as a monadic sentential operator. But nothing prohibits us from introducing a further type of variable Xt that functions syntactically as a binary term-sentence operator. (Zylstra (forthcoming), Section 5.)
Considering as he is all analyses of the relevant, sentential-operator form, rather than just the weird instrinsicality-as-a-sentential-operator instance, he never comes back to consider that maybe the E = N + I approach should be pursued with a binary term-sentence operator. (Another reason for Zylstra's neglecting to do this, perhaps, is that it is Denby's version of the approach that Zylstra considers, and that version - ill-advisedly, as I suggested in a parenthesis near the beginning of this post - fails to deliver the intuitive Finean verdict that containing Socrates is essential to {Socrates}.) But really, that's just the natural view when you think about this. The weird sentential-operator form is just an especially bad version of the E = N + I approach which no one sympathetic to that approach should allow.

I conclude that Zylstra's new paper poses no real threat at all to the E = N + I approach to understanding essence. Rather, the lesson that the friend of the E = N + I approach should draw is that intrinsicality is not to be expressed using a monadic sentential operator. Nor will it do to think of it, in general, as something which relations possess or fail to possess tout court. A relation like the set-membership relation is, so to speak, extrinsic on Socrates’s end but intrinsic on {Socrates}’s end.

In a way, this is really just a criticism about emphasis. Rather than presenting his argument as if it were a serious threat to the E = N + I approach, and then offering a 'glimmer of hope', Zylstra should, in my view, have just presented his argument as showing something instructive about how a friend of the E = N + I should, and should not, try to formulate it.

References

Denby, David A. (2014). Essence and Intrinsicality. In Robert Francescotti (ed.), Companion to Intrinsic Properties. De Gruyter. pp. 87-109.Author-archived version currently available open-access at http://philpapers.org/rec/DENIAE-3.

Fine, Kit (1994). Essence and modality. Philosophical Perspectives 8:1-16.

Zylstra, Justin (forthcoming). Essence, necessity, and definition. Philosophical Studies:1-12. Currently available open-access at the author's Academia.edu page, the URL of which is currently http://vermont.academia.edu/JustinZylstra.