a celebrated sophist of Abdera, was the son of Artemon or Masandrios, and flourished 444 n. c. His poverty had compelled him to adopt the humble trade of a wood-carrier, when some circumstance attracted the notice of his countryman Democritus, and he was admitted as one of his pupils. After he had profited sufficiently by the instruction of Democritus, he proceeded to Athens, where he opened a school, which was attended by all the most illustrious men of the age. Amongst others, Pericles is said to have been his pupil. Protagoras is said to have been the first who set a price on his instruction, and by this means he was enabled to amass a large fortune. Plato, who was his avowed opponent, is willing to allow that Protagoras possessed a lively and fertile imagination, a wonderful memory, and great eloquence; but he was vain, impatient, and presumptuous; he spoke of his rivals with contempt, and of himself with a degree of confidence which excited the admiration of the vulgar. In the Theætetus of Plato we have a summary of the doctrines of this philosopher. Protagoras having in one of his works declared that he could not argue on the nature of the gods, because he was not certain of their existence, he was accused of impiety, and condemned to suffer death, or, according to others, banishment. On his passage to Sicily he suffered