Snowballs and Islands

Members of phased kinds can cease to be members of that kind without ceasing to exist. Of course, as a matter of de dicto necessity, all toddlers are toddlers. But it’s not the case that all toddlers are necessarily toddlers. Members of individuative kinds belong to that kind as a matter de re necessity. A person can’t cease to be a person without ceasing to exist. A statue can’t cease to be a statue without ceasing to exist. If you flatten the statue, it’s not just that it ceases to be a statue; it ceases to exist.

Assuming you’re on board with those cases (i.e., assuming that your modal intuitions aren’t completely defective -- oh snap!), I’m wondering what you think about snowballs and islands. When you flatten a snowball, does it cease to exist, or does it just cease to be a snowball? Suppose you’ve got a low island, and it gets completely submerged every day at high tide. Does it cease to exist at high tide? Or does it continue to exist, but cease to be an island? Or perhaps you want to say that it still exists *and* it’s still an island at high tide? 

I say the snowball survives flattening but ceases to be a snowball, and the island survives being submerged (and probably is still an island). If I’m right about this, it seems that Hawthorne’s complaint that (“barring an anti-realism that none of us should tolerate”) it’s intolerably arbitrary to include islands in one’s ontology and exclude (Hirsch’s) incars. One, but not the other, has extraordinarily weird persistence conditions. Similarly for Sosa’s claim that a realist who lets in snowballs is going to have to let in snowdiscalls as well. Anyway, my question is whether what I say about snowballs and islands seems right to you.

Comments

[Kenny Easwaran]

Your "snap" link doesn't seem to be working properly...

For the island case, what about an island that becomes connected to the mainland at low tide? That certainly continues to exist, but ceases to be an island at some times. Does the Bering land bridge still exist, just in a submerged form so that it's no longer a land bridge?

Maybe a statue can't cease to be a statue without ceasing to exist, but I'm not totally sure that this is the case with sculpture in general. If Duchamp's "Fountain" is removed from the museum and installed in a men's room as an ordinary urinal, then I suspect that it ceases to be a work of sculpture and becomes just a urinal, but it still exists.

[marc moffett]

I get the sense in the island case that it matters a bit as to what the defaults are. There is a difference between a rocky area which is sometimes an island (at very low tide) and an island which sometimes submerged (at high tide). In the first case I might want to say that the island doesn't survive submersion, but in the second case it does.

[Dan Korman]

Kenny,

I’m not sure I agree with everything you say about Duchamp (or, Duchump: zing!). I’m inclined to say that it’s not a sculpture at all. Nothing was sculpted. It’s (identical to) a urinal when it's in the museum, and it’s a urinal when it's out of the museum. It may be art, but that just shows that art is a phased kind. Does that sound right? As for being connected to the mainland, I think it's going to depend on the case (as Marc suggests). It's still an island if, for an hour or so a day, it's connected. It was never an island if it's connected to the mainland above water for the better part of the day. But if it used to always be connected below water, and a thousand years later the water levels recede and it's permanently connected to the mainland, the island has ceased to be an island.

Marc,

I think you’re right that defaults matter, but I disagree about how they matter. I say that the rocky area that peeks out for twenty minutes a day at low tide is not an island at all (even while it’s peeking out). But there’s nothing in that first case that doesn’t survive submersion. (By “survive” I mean: didn’t cease to exist. You too?) It -- the rocky area -- survives, and there’s nothing else of which to ask whether it survived.

[Andrew Cullison]

For what it's worth. I share your intuitions about the islands and the snowballs.

Although, this is weird - my intuition about the snowball is weaker than the island. I have no idea what would explain that.

[marc moffett]

Dan,

I don't know that I agree with your assessment, though I don't strongly disagree. Suppose you were out swimming at low tide and a shark comes cruising after you. You climb onto the exposed rock to get away. Later you report, "Good thing that island was there!" True? Or false but warrantedly assertabile?