There is presentism about existence and presentism about what exists. We have been discussing the latter.
The presentist about what exists seems forced to agree with the eternalist that existence by its very nature is tenseless and not tense-dependent. It seems that he must so agree if his thesis is not to be a tautology. For if the presentist holds that all and only what exists now exists now, then he asserts a merely logical truth, one to which the eternalist will readily assent. So he has to say that all and only what exists simpliciter exists now.
To exist simpliciter is to exist actually, not merely possibly, in a non-tense-dependent way, that is, to exist tenselessly. But what is it for a temporal item to exist tenselessly? It cannot be to exist timelessly for the simple reason that temporal items, items in time, are not timeless items, items outside of time.
(That the number 9, a timeless item, tenselessly exists and tenselessly instantiates such properties as being odd, is not particularly problematic, if you grant that numbers are denizens of the Platonic menagerie. And the same goes for the property of being odd.)
A natural suggestion is to say that a temporal item exists tenselessly just in case it either existed, or exists now, or will exist. But on this disjunctively omnitemporal analysis of tenselessness, presentism about what exists comes out false! Our presentist is then saying that all and only what existed, or exists now, or will exist, exists now. But this is false because, for example, Kepler existed but does not exist now.
I have made two main points.
First, the very formulation of a non-tautological version of presentism about what exists requires that the second occurrence of 'exists' in the formula 'Only what exists now exists' be read tenselessly.
Second, tenselessness cannot be understood as disjunctive omnitemporality.
So what is it for a temporal item to exist tenselessly? If no good answer can be given, then we won't know what we are affirming when we affirm either presentism or one of its competitors.
I hope the reader appreciates that I am not attacking presentism in defense of one its competitors. I am not a partisan in the 'time wars.' I stand above the fray like a good aporetician in keeping with the Maverick method. My aim is to lend credence (though not to prove) that, while the underlying problems are genuine, and important, they are insoluble. None of the extant theories, and indeed no possible theory our minds can construct, is a solution.
An alternative way of viewing the issue is that the presentist denies that there is any such thing as tenseless existence but has no way to say it. In other words, "all and only what exists now exists" should be cashed out as something like "if something does not exist now, there is no sense in which it exists".
This seems like an instance of the problem Quine discusses in "On What There Is":
Posted by: David Gudeman | Tuesday, April 21, 2020 at 12:45 PM
DGs point is subtle.
Where does this leave the anti-realist? Can't he (or she) just insist that the presentist thesis is analytically true, and leave it at that. Leave the burden of the argument on the Realist. If there is any sense in the idea of 'tenseless existence', explain coherently what that sense is.
Posted by: ostrich | Wednesday, April 22, 2020 at 12:05 AM
>>In other words, "all and only what exists now exists" should be cashed out as something like "if something does not exist now, there is no sense in which it exists".<<
You seem to be advocating presentism about existence, as opposed to presentism about what exists. You seem to be saying that to exist just is to be (temporally) present. You might mean this as a semantic thesis: the sense of 'exist(s)' is identical to the sense of 'present.'
One obvious objection to this is that it rules out by semantic fiat the existence of atemporal items, whether concrete (God, e.g.) or abstract (numbers, mathematical sets, etc.)
Posted by: BV | Wednesday, April 22, 2020 at 11:38 AM
Don't numbers and God exist now? If you asked a Christian "Does God exist right now?" Surely he would say "yes".
Or put it another way. A presentist could take this position:
I agree that
(1) all and only what exists now exists
is a tautology, but that is not the definition of my position. The definition of my position is that
(2) present objects exist, past objects don't exist, and future objects don't exist.
(1) can be a tautology and (2) not be a tautology because (1) does not logically imply (2) since (2) references objects that are not referenced in (1)--or so I claim.
Posted by: David Gudeman | Thursday, April 23, 2020 at 06:49 AM
I don't think I was clear in my previous comment. I was not suggesting that God is temporal, I was suggesting that objects that exist timelessly exist at all times, including now, so my reformulations of the presentist position do not take any position on the existence of timeless objects.
Posted by: David Gudeman | Thursday, April 23, 2020 at 06:59 AM
>>If you asked a Christian "Does God exist right now?" Surely he would say "yes".<< Not if he believes that God is eternal as opposed to omnitemporal.
Omnitemporal: in time at every time.
Eternal: not in time.
Posted by: BV | Thursday, April 23, 2020 at 04:27 PM
>> I was suggesting that objects that exist timelessly exist at all times,<<
This is tricky. There are objects that exist spacelessly. Would you say that they exist at every place? Or would you say that they exist at no place? Does the set {2, -2} exist at every place or at no place?
I am inclined to say that it exists at no place and at no time.
Posted by: BV | Thursday, April 23, 2020 at 04:38 PM
"Does the set {2, -2} exist at every place or at no place? I am inclined to say that it exists at no place and at no time."
It's an interesting point that I'll have to think about, but does it apply to my second formulation: "present objects exist; past objects do not exist; future objects do not exist"? Since this statement only makes claims about temporal objects, it still seems to avoid the issue of timeless objects.
Posted by: David Gudeman | Thursday, April 23, 2020 at 09:08 PM
Dave,
You began by saying, >>the presentist denies that there is any such thing as tenseless existence.<<
But surely atemporal items, if any, exist and have their intrinsic properties tenselessly. So if you deny tenseless existence, then you are denying that there are atemporal items. You need to decide between these:
Unrestricted presentism about what exists: for any x, x exists iff x exists at present.
Restricted presentism about what exists: for any x in time, x exists iff x exists at present.
And note that if you are a restricted presentist about what exists, then you cannot be a presentist about existence. That is, you can't say the property of existence is identical to the property of temporal presentness.
Posted by: BV | Friday, April 24, 2020 at 01:52 PM