school of thought that emphasizes the importance of science or empirical science. comte a famous one, has three stage of progression: theological stage. gods, spirits, magic, this would be in terms of religion: metaphysical stage. society explain what"s around them like forces, particles, atoms, universe is made up of particles. this has an intentional entity: scientific. I t does not appeal to crazy phenomena. I t does not explain why something happen, it is observable, empirical knowledge, comes from senses (hearing, touching, etc) things not from senses is spooky, not real. Contrast: aristotle"s essences something has a thing in it: acorn grow because that is how it is, that is their essence, explain why things develop in a certain way. entelechies of early biology 18th-19th: something develops because it is it"s purpose in life and it is it"s goal, this is where things stared.