(I apologize in advance if this has been discussed in the past.)

I was reading some of the links in the 'Cosmological Argument' round up thread on Dr. Feser's blog and came across an exchange between Dr. Feser and the physicist Robert Oerter about causation and Quantum Physics that got me thinking about the arguments that Feser has presented in a couple of his books for the idea that potencies can only be actualized by something else that is actual.  　

This is the relevant post on Oerter's blog: (which I can't include yet because I haven't made enough posts )

In discussing Feser's argument for the principle that "Whatever changes is changed by something else." Oerter quotes from 'The Last Superstition' (p.54) as follows:

Second, and as indicated already, Aristotle holds that even though a thing's potentials are the key to understanding how it can change, this is not the end of the story. An outside source of change is also necessary. For potential gooeyness, say, precisely because it is merely potential, cannot actualize itself; only something else (like heat) could do it. Consider also that if a potential could actualize itself, there would be no way to explain why it does so at one time rather than another. The ball melts and becomes gooey when you heat it. Why did this potential gooeyness become actual just at that point? The obvious answer is that the heat was needed to actualize it. If the potential gooeyness could have made itself actual all by itself, then it would have happened already, since the potential was there already.

He then tries to set out what he sees as the argument contained in the quote above:

1) For a change to happen, a potentiality must become actual.

2) When a potentiality becomes actual, either it actualizes itself, or nothing actualizes it, or it is actualized by something else.

3) A potentiality can't actualize itself (because it is only potential, not actual).

4) A potentiality can't be actualized by nothing (because then there would be no way to explain when the change occurs).

5) Therefore, a potentiality must be actualized by something else.

My complaint is with (4). This step only works if you assume that there is always a way to explain when a change occurs. But what if there isn't?

I didn't read Feser's argument in the same way here because I don't see any explicit mention in it of the possibility of 'nothing' actualizing a potential. As far as I can understand Feser addresses only potentials actualizing themselves (I'm not fully sure what to make of the idea of a potential that neither actualizes itself, nor is actualized by something already actual but is actualized by 'nothing'.).

I was wondering if Oerter started thinking in the way set out above because Feser introduces what I have taken to be a strong argument for the impossibility of a potential actualizing itself ('For potential gooeyness, say, precisely because it is merely potential, cannot actualize itself; only something else (like heat) could do it.') but then seems to consider the idea that it could somehow happen, so as to introduce another argument against the possibility. I was wondering if this extra argument is necessary and if it is raised in dealing with this point by Aristotelian philosophers other than Feser ?

In other posts Oerter goes on to develop an argument from Quantum Physics about shifts happening in the energy level of the electron in a Hydrogen atom that are 'uncaused'. From what I read in one of Feser's replies to Oerter's posts causes in Thomistic philosophy need not be deterministic. So I thought that maybe if 'nothing' seems only to actualize these potentials of electrons when they are part of an atom or molecule, something actual other than the electron itself is responsible for actualizing these potencies in a non-deterministic way. It seems this would be a way of arguing against Oerter's point if an argument was needed (e.g. assuming the idea of 'nothing' actualizing a potency has some legs).

Last edited by FZM (3/23/2016 11:28 am)