Tuesday, December 2, 2025

Disbelief

Suppose Alice believes p. Does it follow that Alice disbelieves not-p? Or would she have to believe not-not-p to disbelieve not-p? (Granted, in both classical and intuitionistic logic, not-not-p follows from p.)

Maybe this is a merely verbal question about “disbelieves”.

Or could it be that disbelief is a primitive mental state on par with belief?

1 comment:

Michael Staron said...

Why would that follow? Couldn’t Alice believe P and not-P? Don’t people sometimes believe contradictory things without realizing it? In which case, she would believe not-P and disbelieve not-P, which sounds odd to me.