Koalemos
It's commonly believed that, in Greek mythology, Koalemos (Ancient Greek: κοάλεμος, Classical Latin: Coalemus) is the deity or daemon of stupidity, found in a play by Aristophanes and a book by Plutarch.
An ancient, unsupported false etymology derives κοάλεμος from κοέω (koeō) meaning "to perceive" and ἡλεός (ēleos) meaning "distraught, crazed".