Can you dispute that “Potency and Act divide being in such a way that whatever is, is either pure act or of necessity is composed of potency and act as primary and intrinsic principles”? Or, to put it more colloquially, can you provide a counterexample to the truth that all things are one thing and have the potential to be other things?
I have been thinking of this, and it’s probably worth providing some examples so we don’t waste time.
First, consider a ball of clay. The clay is
actually round but has the
potential to be a variety of shapes. I can press the clay together, for instance, using my hands to flatten it, and then the clay will
actually be flattened (and, in this case, will still have the
potential to be round again). The clay at any given point is actually something and has some other potentials depending on what it is not but could be, hence the above quote. Its potencies cannot actualize themselves; the clay only flattens because my hands, which are in act, flatten it. But my hands only can flatten it because my muscles are pressing my hands together. My muscles contract and expand only because certain ions are released into specialized cells, but those ions are only released because action potentials are reaching muscle cells.
At any given point that I am flattening the clay, there is a
per se series of causes (the clay flattening, my muscles contracting, ions bonding to specialized proteins, orbiting electrons forming pairs), which is simultaneous and in which the causes I’ve named instrumentally have
derivative causal power*. The clay does not flatten itself but by what is imparted to it. The surface of my hands do not move themselves but are moved by my muscles, which only contract because calcium ions are bonding to intracellular structures, which is only occurring because of the interaction between calcium ions and proteins. But it would be impossible for every cause in a series to have derivative causal power; if no cause has non-derivative causal power, then there would not be any causal power in the series, so there must be something which has causal power in itself without being moved itself, hence Pure Act. (This is why an infinite
per se causal series is impossible: if all causal power were derivative, then there would not actually be any causal power.)
*There is also a
per accidens causal series, since the firing of the action potential at the brain, its traveling to the muscles in my arms, and the closing my hands are not all simultaneous. However, examining any single instant of that
per accidens causal series would reveal a
per se causal series.
So there is really no conflict with modern physics. I think few people realize how scientifically unintrusive are the metaphysical principles on which the First Way rests (but since modern science implicitly relies on and presupposes them, it is unsurprising that they do not and could not conflict with science proper). Actuality and potentiality are, I think, difficult to deny. A slightly simpler example would be hydrogen and oxygen atoms. They are
actually H2 and O2, but inherent in them is the
potentiality to combust and form H2O if
acted upon by, say, a flame. But they only do so when
acted upon. They do not combust without being
acted upon; even “spontaneous combustion” involves molecular action. Before they are acted upon, they merely have combustion with each other in potency, as something inherent in their forms as hydrogen and oxygen molecules. (They also have other potencies. Oxygen, for instance, could alternatively oxidize iron or other metals.)
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