This is a post from the old blog. It originally appeared on 27 May 2008 and appears now slightly redacted.
In this blogging game you throw out your line and damned if you don't snag a good catch now and again. I dredged up Peter Lupu from the Internet's vasty deeps long about January  and I'm glad I did. He's smart and has an admirable passion for philosophy, that highest and most beautiful of all human pursuits. Even more remarkable, perhaps, is his ability to keep his passion alive in the midst of the mundane quest for the buck that keeps the wolf from the door, the lupus from the Lupu.
Enough of cleverness and encomium. Back to work.
In a comment [now lost in the ether], Peter mentions three points of difference between me and him on the topic of existence.
First, he denies my assertion that Frege and Russell are eliminativists about singular existence, though he agrees with me that for neither is existence attributable to individuals. Let's leave this topic for later. Second, Peter thinks that Kant denies that existence is a property of individuals and that Kant anticipates Frege and Russell on existence. This is a bad mistake that almost every analytic philosopher makes; Peter is in truly excellent company. It too deserves a separate discussion. [And receives it in a forthcoming article, "Existence: Two Dogmas of Analysis."]
Third, Peter seems to think that the fact that everything exists shows that existence cannot be a property of individuals. This is the question I propose to discuss in today's installment.
We agree: everything exists, which is to say: there are no nonexistent items, pace Alexius von Meinong. Existence, then, is not classificatory: it does not divide a sum-total of items into two mutually exclusive and jointly exhaustive subgroups, the existent items and the nonexistent items. There are no nonexistent items. Peter mentions rationality, weight, and temperature. Some things have weight, some things don't. And the same goes for the other properties. Because some things are rational and others are not, Peter suggests that it makes sense to inquire into what it is for something to be rational. But since absolutely everything exists, it makes no sense, Peter suggests, to inquire into what it is for something to exist. Existence lacks content due to a failure of contrast. Peter seems to be offering us a
1. If a term 'F' has an explicable content, then there must be items to
which 'F' does not apply.
2. There are no items to which 'being' or 'existent' does not apply.
3. 'Being' or 'existent' does not have an explicable content..
In point of validity, this argument is unobjectionable: it is an instance of Modus Tollens. But it is unsound. The following consideration suffices to refute the first premise. Since everything is self-identical, it is true to say of any particular thing that it is self-identical. But 'self-identical' is not rendered either without sense or content by the plain fact that nothing is self-diverse. Or consider the proposition that every event has a cause. Suppose it is true. (And suppose that everything at bottom is an event.) Then every event has the property of being caused and no event lacks this property. But it does not follow that we cannot ask what it is for an event to be caused. The different theories of causation would be answers to this question.
I don't think we need to waste any more words on the first premise. It is obviously false.
But even if you insist that (1) is true, there is still a problem with the argument. Although (2) is true, it does not have the implication one might think it to have. One might think that if everything exists,
then it is unintelligible to suppose that there is a difference between existence and nonexistence. But this is a non sequitur. For although it is true that there is nothing that does not exist, a contingent being that does exist is possibly such that it does not exist. So there is a contrast after all. It is the contrast between existence and possible nonexistence. Each contingent individual faces the contrast: existence versus possible nonexistence. With apologies to the Bard, "To be or [possibly] not to be, that is the question."
It is quite clear that the difference between existence and nonexistence cannot be explained by giving examples of existents and examples of nonexistents. Pace Meinong and the Meinongians, there are no examples or instances of nonexistents. One could put this by saying that the existence/nonexistence contrast does not show up extensionally and indeed cannot. But how it is supposed to follow from this that there is nothing real in things that grounds the application of 'exists' to them? I exist. I am not nothing. But I might never have come to exist. And given that I do exist now, I might not have existed now. This 'property' of existing is of course no ordinary property. It is not like the properties of being red, or ripe, or spheroid. But I have it and I might not have. And so there is a contrast, situated at the level of each contingent individual, between its existence and its possible nonexistence.
Peter claimed that since absolutely everything exists, it makes no sense to inquire into what it is for something to exist. I just rebutted his claim by pointing out that Contrast Arguments are in in general unsound and by pointing out that, with respect to existence there is after all a contrast, the contrast between the existence of a contingent individual and its possible nonexistence.
It seems to me that there is a rather obvious mistake that one ought to avoid. And that is to assume that existence or Being is a highest what-determination. The mistake is to think of 'being' as a maximally general term which, due to its all-inclusive extension, is virtually nil in intension. Here is an example of how the mistake is made:
The distinction between 'being' and, for example, 'dog,' is then a
distinction between the more general and the less general. This is
a logical or cognitional distinction, which does not necessarily
reflect anything in the nature of things. Nor does it necessarily
point to any real composition within things. It is analogous to the
distinction made between 'animal' and 'dog' when it is said that
Rover is a dog and Rover is an animal, which distinction does not
point to two distinct principles within Rover: dog and animal.
Rover is a dog who is an animal, an animal who is a dog. His being
a dog and his being an animal are the same in him, even though
there are other animals. Similarly, Rover is both a being and a dog:
there are other beings, but this does not change the fact that
for him, to be a dog is to be a being, to be a being is to be a
dog. (John N. Deck, "Metaphysics or Logic?" The New Scholasticism,
Spring 1989, 232-233)
This passage shows that Deck is thinking of being as a highest genus. Rover is a dog, an animal, a living thing, a physical thing . . . a being. On this way of thinking, being is the most general
what-determination. You can arrive at it by climbing the tree of Porphyry to the very top. But if anything is clear, it should be that Being or existence is not a summum genus or genus generallisimum as Aristotle pointed out at 998b22 of the Metaphysics. And as Kant pointed out in his famous discussion, Being or existence is not a reales Praedikat: Being or existence is no part of what a thing is.