So, the very existence of scientists themselves, qua perceiving and thinking subjects, presupposes the reality of change. But the reality of change, the Aristotelian argues, in turn presupposes the distinction between actuality and potentiality (Edward Feser, Aristotle's Revenge: The Metaphysical Foundation of Physical and Biological Science, 88)
Correction: Initially, I thought this was of the logical form of affirming the consequent. It is not. Rather, the problem is with the premises themselves, which posit a false causal relationship between the items mentioned.
I don't see it.
ReplyDeleteTo me it seems that Feser is saying something like:
If scientists exist, then change is real.
If change is real, then there is a real distinction between act and potency.
Therefore, if scientists exist, then there is a real distinction between act and potency.
This seems valid.
Could be wrong, though, so could you explain?
Feser's argument is as follows:
ReplyDeleteP1: If change exists, then scientists (qua perceiving and thinking subjects) exist.
P2: If the distinction between actuality and potentiality exist (as understood in Aristotelianism), then change exist.
P3: (Implied) Scientist exists
C: Therefore, Aristotelianism is true, because scientists exist.
The premises are as follows because Feser framed the argument in the form: X presupposes Y. Now, if X presupposes Y, then if Y exists, X must exist. If Y exists, X cannot not exist. Thus, the form of the relationship is "If Y, then X." (You can use a truth table to check it out).
As it can be seen, the argument is of the form of affirming the consequent.
I agree that your gloss of Feser's argument does affirm the consequent. However, it seems to be a misrepresentation of what Feser is saying.
ReplyDeleteThe problem seems to be this. You said:
Now, if X presupposes Y, then if Y exists, X must exist.
But you seem to have put things backwards. If X presupposes Y, then if X exists, Y must exist. For instance, since my existence presupposes my parents existed, we can conclude, "If I exist, then my parents existed." But we wouldn't say, "If my parents existed, then I exist."
If perception is a change, then scientists qua perceiving beings can only exist if change is real. Hence, as I put it: if scientists exist, then change exists. Likewise with the second premise. That strikes me as a straightforward reading of what Feser is claiming.
Insofar as Feser believes God did not have to create, or create a world with scientists in it, this gives good reason to think he would reject both P1 and P2 of your gloss on his argument, and therefore, some reason to think he did not intend your argument by what he wrote.
Since there would be a changing world without any scientists, he would not say "If change exists, scientists exists". And in the second case, only God exists. Feser says God is purely actual. So no change would occur. And yet, the distinction between act and potency would still be true, he's say, since whatever could be would have to be in some way potential.
Both for reasons internal to the quotation and external to it, I think my gloss is preferable.
Hmm, ok, I see where I had erred. I had confused Feser's argument with the propositions themselves, which are question begging propositions.
ReplyDeleteThanks for the correction