Kant's solution was an epistemological dualism : we cannot know the thing-in-itself ( " Das Ding an Sich " ) beyond our mental representation of it.
2.
Na�ve realism is known as " direct " as against " indirect " or " representative " realism when its arguments are developed to counter the latter position, also known as epistemological dualism; that our conscious experience is not of the real world but of an internal representation of the world.