plato is famous for developing the idea of the theory of forms. the concept of the world of forms states that actual things of a common nature are imperfect representations of a perfect conceptual thing. for example, there are brown dogs, grey dogs, old dogs, skinny dogs etc. that are all imperfect variants of the perfect form of “dogness”. this led him to believe in “a world of forms” and that our world is a shadow of the world of forms. he thought that all perfect forms of things came from pure perfection itself, which can be seen as god. he thought the human ability to know of nonspecific conceptions of things was proof humans had immortal souls that had been in the world of forms.