When a person argues ab absurdo, he or she is trying to establish the validity of her or his position by pointing out the ridiculousness (absurdity) or foolishness of the opponent's arguments.

Although an argument ab absurdo "demolish" an opponent's position in debate, it does not necessarily prove the validity of that person’s position. The only thing that may be accomplished is that the ab absurdo argument may make the other person seem to be foolish or illogical.