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Philosophy

Counterfactuals and Possible Worlds Semantics

Quick fact

Classical logic's truth table says that 'If P, then Q' is true whenever P is false—so the claim 'If the moon is made of cheese, then 2+2=5' would be true. This paradox shows why counterfactuals need a richer semantic framework, one that compares actuality with nearby possible worlds.

Why this is interesting

If I had not dropped the glass, it would not have shattered. What makes that statement true? The glass did break, so how do we judge a claim about a scenario that never happened?