Idea World

This world is unreal, uneternal, and always change. Idea world is the truth world. The unreal/ sense world is only the shadow of the idea world. Say an example, a tree. In this world got lots of kind of tree. Those trees are not the same each other. Not only the shape is difference, it also does not eternity. Tree grows, dies, and extinct. But the idea about tree is remain...
(by Plato)