Remark on Free Will

Any one [Fact] can either be the case or not be the case, and everything else remain the same.

—Wittgenstein, Tractatus Logico-Philosophicus, 1.12

This is true by Wittgenstein's notion of Fact, but it raises a broader question: To what extent is an entity (in particular, the human subject) determined by its surroundings? Instead of thinking about this in terms of causality, let's think about this logically. By logically, I mean the following: There is a multitude of possible Worlds (in the sense of Leibniz) where possibility is determined by the laws of logic; Instead of asking "Am I free to do X?" I'd ask "Is there a possible world, in which do X, and all prior events stay the same?"