Western physicalism, that only physical things exist, evolved from the earlier materialism that only matter exists when science advanced to describe more than just matter. The distinction between materialism and idealism traces back to Socrates, a Greek philosopher who lived when the word meant lover (philo) of wisdom (sophia). His pupil, Plato, argued that pre-existing ideal forms generate things, a view later called idealism, that something non-physical is the ultimate foundation of all reality. Aristotle, who was Plato’s student, didn’t deny this, but held that a thing’s substance is its material cause, and how other matter changed it is its efficient cause, which supported materialism. Western science then focused on Aristotle’s physical causes, while western religion focused on Plato’s non-physical causes, but both accepted the physical world as real in itself.
Plato’s premise was that a non-physical reality creates our world as the sun creates shadows on a wall [1]. This led western Gnostics to conclude that the world was a lie, created by a demiurge who was ignorant of the original reality [2]. In the East, Chan Buddhism held that a universal essence of mind generates the observed world like bubbles on a sea, and Hinduism saw the physical world as Maya, an illusion created by God’s play (Lila). Yet at any time, only a few ever truly believed that the physical world wasn’t real in itself.
[1] In his analogy, people tied up in a dark cave with their backs to its exit see their shadows on the cave wall, created by sunlight from the outside, and take them to be reality.
2] In this story, the original fullness (Pistis Sophia) tries to make something new from herself but accidently creates a monstrous demiurge (lesser god). Ashamed she quarantines him. He being alone and thinking only he existed, creates our world in his own image, entrapping Sophia’s essence in a false physical world.