Darwin said that as more individuals are produced than can possibly survive, there must be a struggle for existence. There's no agency behind natural s. That's just a word we use to describe what's going on in nature. i always thought his opening chapter the origin of species on artificial selection. Pigeon breeders, for example, was i understand what he was doing, but it's a bit misleading because there are pigeon breeders.
In this AMA Dr. Michael Shermer answers your questions about evolution and creationism, intelligent design theory, the hard problem of consciousness, the origins of morality, how science deals with anomalies, to what extent humans are naturally rational or irrational / skeptical or gullible, and why there is something rather than nothing.