PPT Slide
Ancient & Medieval Philosophy -- David L. Rouse
1. The material cause is that out of which a thing comes to be. It is what the thing is made of.
2. The formal cause is the shape of the thing, but also its essence. It is why it is the kind of thing that it is.
3. The efficient cause is that which brought about the change leading to the thing’s existence.
4. The final (telos, telos) cause is the purpose or function, the “for the sake of which” the thing exists.