Consider that Aristotle is the first to have written systems by which to understand and criticize everything from pure logic to ethics, politics, literature, even science.
He theorized that there are four “causes”, or qualities, of any thing in existence: the material cause, which is what the subject is made of; the formal cause, or the arrangement of the subject’s material; the effective cause, the creator of the thing; and the final cause, which is the purpose for which a subject exists.
All philosophers since Aristotle have had something to say on the matter, and absolutely everything that has been said, and perhaps can be said, is, or must be, based on Aristotle’s system of it: it is impossible to discuss causality without using or trying to debunk Aristotle’s ideas.Aristotle is also the first person in Western history to argue that there is a hierarchy to all life in the Universe; that because Nature never did anything unnecessary as he observed, then in the same way, this animal is in charge of that animal, and likewise with plants and animals together. His so-called “ladder of life” has eleven rungs, at the top of which are humans.
The Medieval Christian theorists ran with this idea, extrapolating it to the hierarchy of God with Man, including angels. Thus, the angelic hierarchy of Catholicism, usually thought as a purely Catholic notion, stems from Aristotle, who lived and died before Jesus was born. Aristotle was, in fact, at the very heart of the classical education system used through the Medieval western world.
Aristotle had something to say on just about every subject, whether abstract or concrete, and modern philosophy almost always bases every single principle, idea, notion or “discovery” on a teaching of Aristotle. His principles of ethics were founded on the concept of doing good, rather than merely being good. A person may be kind, merciful, charitable, etc., but until he proves this by helping others, his goodness means precisely nothing to the world, in which case it means nothing to himself.