This post might wander all over, as I jot down thoughts that seem relevant.
Ding an sich
Kant used the expression “Ding an sich,” which is usually translated as “the thing in itself”. Kant’s idea was that we cannot know the world in itself; we can only know the world as we experience it.
This has turned out to be a controversial view. Many people disagree with Kant about this. However, I am inclined to agree, though perhaps my reasons are different from those of Kant.
In Genesis 1:2, we read “And the earth was without form, and void; and darkness was upon the face of the deep.” I am inclined to see that as a pretty good description of the world in itself, although I doubt that I am using that in the way the author(s) of Genesis intended.
If we attempt to describe the structure or form of the world, we may find ourselves using words such as “texture”, “height”, “color”. We use these words to express human concepts. When we talk of the world in itself, we should limit ourselves to what can be said without depending on human concepts. And there isn’t much at all that can be said.
As for that “darkness” part of the Genesis text, we can reasonably assume that the earth was bathed in electromagnetic waves. But most electromagnetic waves are not visible to us. Our sight depends on a narrow range of wavelengths. That we happen to be able to sense those wavelengths is part of our biology. So we should exclude that as part of what we consider the world in itself.
Kant contrasted this with the world of appearances, or the world that we experience. It seems entirely reasonable to me, that the way we experience the world is very different from the way that an ant experiences the world, or the way that a bird experiences the world or the way that a bat experiences the world. So when we talk of the world in itself, we should consider only what is observer independent. But we cannot know anything apart from observation. Hence my agreement with Kant’s view.
The Heretical Philosopher 