I think I've come up with an interesting way to show that the first mover is pure act. Now I'm a novice to Thomism so I may unknowingly have an obviously invalid argument. Here it goes:

I know some people will concede the point that Aquinas' First Way gets us to a being who is the source of all causal power, who actualizes all potentials without having to have a potential, relative to its own causal power, actualized. That is, they'll say that the being's causal power need not be actualized by a prior member but there may still be unactualized potentials irrelevant to its causal power. And perhaps these potentials can never be actualized, perhaps they're just there. But, nonetheless, they're still there which would be enough to rob the first mover of the status of being pure act.

Garrigou-Lagrange talks about the transition from potency to act (becoming) as something which involves a "union of diverse things." For instance, water which is room temperature becomes boiling. Now this is interesting because it means that potentials stand in contrary relation to actualized potentials. That is, the potential for the water to be frozen, or to be lukewarm, or to be freezing, stands in contrary relation to the fact that it isn't any of those--it's actually boiling. And it's actually boiling because something already in act is actualizing its potential to be boiling, namely, a burner. So, a potential stands in contrary relation to an already actualized potential--e.g. potentially cold and actually hot, potentially dry and actually wet, potentially on the table and actually on the counter. The reason why they're contrary is that these potentials can't be in act at the same time (you can't have water be boiling alongside its actualized potential to be frozen).

This would entail that if the first mover had some potentials irrelevant to its unactualized causal power, then those potentials would stand in contrary relation to an already actualized potential. But if there exists an already actualized potential then there must be something which actualizes that potential. Therefore the first mover wouldn't really be the first mover since something exists outside of it which actualizes its potential. So we can conclude that the true first mover cannot have any potentials whatsoever--it must be pure act.


 

Last edited by RomanJoe (5/18/2017 1:26 pm)