There is no point in talking to someone who seriously claims that he doubts everything, as he is not a man. He is, as Aristotle expressed, similar to the trunk (φυτού ὅμοιος). He is not fit to become a philosopher. He is rather teasing for the sake of teasing. Jewish philosopher, Saadija Fajjumi from the tenth century, in his work “Knowledge of faith and philosophy” advises to starve such men and beat them with sticks until they acknowledge that they consciously and definitely feel hunger and pain. Truly that is an effective means to bring them to repentance.
Franciszek Kwiatkowski – Perennial philosophy p>