This thesis makes a thorough analysis of Plato's concept of Idea by referring to many important Plato's dialogues, with studying some other concepts, such as nous, noesis, auto, etc.

它作为事物之自身,乃是事物的,作为在,乃是事物之应的之概念,而它同时又是事物的理想在,构成了事物的目的,这样,它在根上是体论、逻辑学和目的论三者的统一。