Wednesday, November 11, 2009

Easy “Difference-Making” Properties?

Last week we discussed Cameron’s 'Truthmaking for Presentists,' very cool paper!

Bracketing concerns about a notion of indeterminacy whose source is not semantic (nor epistemic) and about the notion of indeterminate truth, we devoted part of the discussion to Cameron’s contention that insatisfaction with “Lucretian” properties like being such as to have been a child motivates restriction to difference-making properties as candidates for truthmaking, understood as properties “the instantiation of which at a time makes a difference to the intrinsic nature of the bearer at that time”.

If I understood them correctly, both Marta Campdelacreu (in attendance) and Pablo Rychter (virtually) independently worried that some properties that would count as difference-making for Cameron seemed insatisfactory for truthmaking in just the same way than “Lucretian” properties were. Take an intrinsic property Ross presently instantiates, say being currently sitting. It would seem as unsatisfactory as before that the presentist used the property of being such as to have been a child and currently sitting in the truthmaker for the truth that Ross was a child. But the property is difference-making for him, given that
(*) Ross has the intrinsic nature at the present that he has partly in virtue of instantiating being such as to have been a child and currently sitting at the present.
(Notice that it won’t do, it seems to me, to reject (*) on the basis of:
(#) Ross has the intrinsic nature at the present that he has partly in virtue of instantiating being currently sitting at the present.
For, arguably, if (#) is true then (*) is also true. See the axiom of subsumption in Fine’s (1995) logic of essence, and the discussion of the conjunction thesis for truthmaking in López de Sa (2009).)

1 comment:

Ross Cameron said...

Thanks Dan!

Basically, I want to do what you think won't do. I want to hold the following: that if you have your present intrinsic nature partly in virtue of having the property F and it's not true that you have your present intrinsic nature partly in virtue of having the property G, then it's not true that you have your PIN partly in virtue of having the conjunctive property being F and G. All the work is being done by F, none at all is being done by G, so what settles your PIN is your being F, nothing to do with G, so the conjunctive property F&G isn't helping settle your PIN, only the one conjunct is.

Now, maybe there's a liberal notion of in virtue of according to which (*) follows from (#). (Maybe!) But as long as there's *some way* for me to make the required distinction, that's all I want. So perhaps the only admissible properties are those that play a role in the minimal difference-making base. I can't see a reason to doubt that there's some way of distinguishing difference-making properties such that a conjunctive property with a difference-making property as a conjunct doesn't itself automatically count as a difference-making property.