Did you wake up early this morning? Can you always answer that by a clear yes or no? When do you draw the limit between them? At 7:30? So if you woke up at 7:29:59 you would answer Yes and later No.

Instead you could put a distribution (but NOT a probability distribution) for belonging in the set of early that would look something like this.

If you wake up before 6:30 it would definitely 100% be early and at 8:30 it would. Or at 8:30 it would not at all, 0%, be early. Between there we would put some kind of partly belonging to Early rises.

In probability it is either or, but lack of knowledge makes us, but put a probability on what it is. In fuzzy logic, it is a bit of both at the same time.