Aristotle -> Aquinas -> Atheism, Part 7
Proof Five: Final Cause
The final cause of Aristotle is to consider what is a things end, purpose, or use. The last proof revolved around form, and this one revolves around function or “the end, that for the sake of which a thing is done”.
Aristotle found acting upon ends is not simply the domain of humans, but even of nature.
“If, then, a swallow makes its nest and a spider its web both naturally and for some end, and if plants grow leaves for the sake of the fruit, and send roots down rather than up for the sake of nourishment, it evidently follows that this sort of cause is among things that come to be and are by nature.” (Physics, Book 2, 199a)
Further, things without awareness act to attain ends, “We see that things which lack intelligence, such as natural bodies, act for an end, and this is evident from their acting always, or nearly always, in the same way, so as to obtain the best result” (Aquinas). More simply put, a rock always falling when dropped is attaining its’ best result, its’ natural end.
Taken in it’s broadest form, this cause of Aristotle might be understood as: matter expresses itself according to the laws of physics; with Aquinas adding: laws need to be created by intelligence, whom we name “God”.
Dawkins response that we have evolution, and in this he misses the grandeur Aristotle. Evolution does nothing to explain the four fundamental forces in the universe; or even more broadly: why do things follow laws at all? Physics is great at noticing the laws, but has yet to take even the most rudimentary guess as to why laws exist. Aristotle shows that air does not rise because of luck (as he notes Empedocles believes in Physics, Book II, 196a), but rather that all of nature acts out of principles (the laws which physicists discover). Aquinas echoes this when he writes, “it is plain that not fortuitously, but designedly, do [natural bodies] achieve their end”. The designs of nature are enforced in laws, like that of gravity or magnetism. These laws must have a source, just as other causes needed a source, and Christians similarly call this source of law God.