On page 21 of Nietzsche's Beyond Good and Evil, I found the following quote:
Suppose someone sees through the boorish naivete of this famous concept of "free will" and manages to get it out of his mind; I would then ask him to carry his "enlightenment" a step further and to rid his mind of the reversal of this misconceived concept of "free will": I mean the "un-free will," which is basically an abuse of cause and effect. We should not erroneously objectify "cause" and "effect" like the natural scientists do (and whoever else thinks naturalistically these days) in accordance with the dominant mechanistic stupidity which would have the cause push and shove until it "effects" something; we should use "cause" and "effect" only as pure concepts, which is to say as conventional functions for the purpose of description and communication, not explanation. In the "in-itself" there is nothing like "causal association," "necessity," or "psychological un-freedom."
I am somewhat confused by this position. First he declares that the "causa sui" is absurd - that we cannot be the cause of our own existence. I assumed from this and other quotes from the book that Nietzsche believed our existence was caused by something else. However, this quote complicated things for me.
Since he makes a specific point to assert that causality doesn't apply to the "in-itself," it seems as if he is only stating that the existence of a thing doesn't need a cause. After all, for there to be a total absence of causation in the universe, we would have to be applying an incredible amount of organization to a completely random mish-mash of disconnected reality-states while perceiving them.
A few sentences after the quote, he attempts to replace the concepts of free and un-free will with strong and weak will, which still seems to imply lots of causality to me (I still don't fully understand Nietzsche's definition of the word "will").
How far does Nietzsche's skepticism of causality go, and can someone provide a semi-simplified explanation of Nietzsche's own vision of a world without causation?