Why Paradoxes Matter

The grandfather paradox is valuable not because time travel is likely, but because it exposes hidden assumptions in everyday thinking. We assume cause comes before effect, that the past is fixed while the future is open, and that our actions have straightforward consequences.

The paradox shows these assumptions, however useful, are not logically necessary. Physics can describe universes where causation runs backward and where logical consistency outranks human intuition about how time should work. Wrestling with such puzzles sharpens thinking by forcing you to examine foundations you normally take for granted.