Philosophy
The Metaphysics of Causation and the Counterfactual Theory
Quick fact
The counterfactual theory of causation, famously developed by philosopher David Lewis, holds that an event C causes an event E only if E counterfactually depends on C—meaning that if C had not occurred, E would not have occurred either. This idea turns causation into a matter of what would happen in nearby possible worlds.
Why this is interesting
You know that a window breaks because a rock hit it. But what does 'because' mean? Is it just that the rock hit it first? And what if the window would have shattered anyway from an explosion at the same moment?