I thought it was a mistake because he pronounced it “coincide-dental.” Like a fancy variation on the word “coincide.”

Mistake or not, it had never occurred to me until that moment that coincide and coincidental are variations on the same concept (which they are).

In my mind, “coincide” always meant “at the same time,” whereas “coincidental” always meant “chance occurrence.”

A good reminder that what we believe to be true affects what we hear (or don’t).