Protagoras

Protagoras (c. 490 – c. 420 BC) was a pre-Socratic Greek philosopher and is numbered as one of the sophists by Plato. In his dialogue, Protagoras, Plato credits him with having invented the role of the professional sophist.
He also is believed to have created a major controversy during ancient times through his statement that, "Man is the measure of all things", interpreted by Plato to mean that there is no absolute truth, but that which individuals deem to be the truth. Although there is reason to question the extent of the interpretation of his arguments that has followed, that concept of individual relativity was revolutionary for the time, and contrasted with other philosophical doctrines that claimed the universe was based on something objective, outside of human influence or perceptions.
== Tossup Questions ==
# The two central figures of this text are compared to "two bald men searching for a comb" in Soren Kierkegaard's dissertation. The first paragraph of J. S. Mill's Utilitarianism cites this text as foundational. It claims that pleasure is the good and one cannot be overcome by good, so the state of being "overcome by pleasure" can only result from ignorance. One man in this text describes how all species but humans received a special power at creation because Epimetheus forgot. Several men lift the ailing Prodicus out of bed in this text, in which the poetic lines from Simonides, "for a man to become good is truly hard" and "hard it is to be good," are contrasted. This dialogue is set in the house of Callias, and concludes with Socrates undermining his own argument by stating that the central concept is knowledge, and knowledge can be learned. For 10 points, name this Platonic dialogue in which Socrates debates whether virtue can be taught with a Sophist who claimed that "man is the measure of all things."
# This work's title character claims to be old enough to be the father of all present and references his time as a confidant of Pericles, whose son Paralus is a character. This work is referenced in the Nicomachean Ethics for its discussion of the weakness of the will, while, in Utilitarianism, Mill argues that Socrates presents a utilitarian argument in this dialogue. Socrates appeals to Prodicus to resolve an apparent contradiction about "being versus becoming good," which the title character introduces by quoting a poem attacking Pittacus by Simonides. It opens by discussing Alcibiades' beard and this dialog's title character is considered the first to call himself a sophist. Questioning whether virtue may be taught, for 10 points, identify this dialogue named for the man that claimed "Man is the Measure of All Things."