You
need these to
prove an accusation to be true. Proofs must be
physical, and witnesses are NOT proofs.
Dude 1: "Your breath
smells so bad! Brush your
teeth!"
Dude 2: "My breath smells
great, you have no proofs!"
Dude 1: "Literally everyone can smell your bad breath! There are so many witnesses."
Dude 2: "UM, WITNESSES ARE NOT PROOFS!"