My Existence and My Possible Nonexistence

Leo Mollica made a good objection to my earlier argument, an objection I  need to sort out.  I exist, but I might not have existed.  How might a thin theorist translate this truth?

On the thin theory, my existence is my identity-with-something.  It follows that my nonexistence is my diversity-from-everything, and my merely possible nonexistence is my diversity from everything in one or more merely possible worlds.  But -- and this I take it is Leo's point -- I needn't exist in merely possible world w for it to be true in w that I am diverse from everything in w.  So w is not a world in which I am self-diverse, but simply a world in which I am diverse from everything in w.  Had w been actual, I would not have been self-diverse; I would not have existed at all, i.e., I would not have been identical to any of the things that would have existed had w been actual.

To put it another way, on the thin theory, my actual existence is my self-identity, my identity with me.  Opposing this reduction of singular existence to self-identity, I argued that if my existence is my self-identity, then the possibility of my nonexistence is the possibility of my being self-diverse -- which is absurd.  Mollica's rejoinder in effect was that my possible nonexistence is not my possible self-diversity, but my possible diversity from everything distinct from me.

I could respond  by saying that this objection begs the question by assuming the thin theory.  But then Mollica could say that I am begging the question against him.  Let me try a different tack.

If I am diverse from everything in w, but I don't exist in w, then something must represent me there.  For part of what makes w w is that it lacks me.  It is essential to w that it not contain me. But how express this fact if there is no representative of me in w?  Now the only possible candifdate for a representative of me in possible worlds in which I do notr exist  is my haecceity-property: identity-with-BV.  If there is such a property, then it can go proxy for me in every possible world in which I do not exist, worlds which  in part are  defined by my nonexistence.

So it seems that Mollica's objection requires that there be haecceities such as identity-with-BV, and that these be properties that can exist unexemplified.  But now two points.

First, there are no such haecceity properties for reasons given elsewhere, for example, here.

Second,  if haecceities are brought into the picture, then we are back to the Fregean version of the thin theory according to which 'exists(s)' is a second-level property.  But what I have been pounding on is the latest and most sophisticated version of the thin theory, that of van Inwagen.  And we have seen that he rejects the view that 'exist(s)' is second-level.

Comments

[Leo Carton Mollica]

Thank you kindly for the post! I'm quite flattered. Sorry for the delay in commentary: I've been chewing over the content.

I think, though I'm not quite sure, that you've captured my main point, which was that your original formulation of the argument gave rise to a contradiction (that at some possible world I both exist and do not exist), unless you equivocate on the modal operator "possibly".

You charge me with needing to affirm the existence of haecceities, on the grounds that "[i]f I am diverse from everything in w, but I don't exist in w, then something must represent me there," and that "something" can only be an haecceity. But I think there is another way out of the difficulty, inspired by Arthur Prior. One of your original premises, and one which was needed to give rise to my contradiction, was "Possibly, BV does not exist," which you claimed was self-evident. But I'm not so sure: certainly, it is not necessary that I exist, but can it be possible that I not exist? That would seem to require a world at which there are no facts about me (since, if I don't exist, there cannot be facts about me), and there is the fact that I do not exist, which is a contradiction. So, my preferred resolution is that it is not possible that I do not exist, and that in worlds at which it is not true that I exist propositions about me do not exist, or are unstateable (Prior makes this notion of stateability more precise).

So, in summary, I'd say that I don't need to posit a representative of me in worlds at which I am identical with nothing because at those worlds it is not true (or false) that I am identical with nothing; the proposition is unstateable. Since this involves denying the truth of "Possibly, BV exists", which was required for my criticism of your argument, I seem to sidestep the problem. Am I being clear?

As a final note, I don't consider myself a thin theorist: you and others have helped convince me that singular existence is a genuine predicate-cum-property not reducible to the truth of any general existential statement. My criticism concerned the argument, not its conclusion.

[Leo Carton Mollica]

An edit: In my penultimate paragraph, I should have said, "Possibly, BV does not exist," not "Possibly, BV exists."

[Bill Vallicella]

Leo,

You grant that I exist, and you grant that it is not necessary that I exist. But you also seem to be saying that it is not possible that I not exist.

But this is very hard to swallow given the modal equivalence:

~(Nec p) iff Poss ~p.

[Leo Carton Mollica]

Dr. Vallicella,

Yes, it is an admittedly counterintuitive consequence of this account that possibility and necessity are not interdefinable. So I deny the modal equivalence.