Philosophy
Possible Worlds and Modal Realism
Quick fact
Modal realism, defended by philosopher David Lewis, posits that every possible world – even those where dinosaurs never went extinct – is just as concrete and real as the one we inhabit.
Why this is interesting
We often say 'it might have been otherwise' – but what does that really mean? Is there a sense in which other realities truly exist, right now, just out of reach?