Protagoras is generally considered to be the first Sophist. He was known for his skeptical attitude towards traditional beliefs and his emphasis on the importance of individual opinion.

Protagoras's central tenet was that "man is the measure of all things." This means that there is no objective truth or reality, but rather that truth and reality are relative to the individual.

Gorgias's most famous work was "On Nature or the Non-Existent." In this work, he argued that nothing exists, that if something did exist it could not be known, and that if it could be known it could not be communicated.

Hippias was a mathematician and astronomer. He was also known for his skill in rhetoric and his knowledge of history.

Thrasymachus's most famous work was "On Justice." In this work, he argued that justice is the advantage of the stronger.

The Sophists were criticized for being too skeptical, too relativistic, and too focused on rhetoric and persuasion.

The Sophists helped to lay the foundation for the skeptical tradition, the idea of relativism, and the emphasis on rhetoric and persuasion.

Plato was the Sophist who was known for his theory of the "noble lie." This theory states that it is sometimes necessary to tell a lie in order to maintain social order.

Thrasymachus was the Sophist who was known for his argument that "might makes right." This argument states that the strong have the right to rule over the weak.

Socrates was the Sophist who was known for his argument that "virtue is knowledge." This argument states that the only way to be virtuous is to have knowledge of what is good and right.

Socrates was the Sophist who was known for his argument that "the unexamined life is not worth living." This argument states that it is important to constantly examine one's life and beliefs in order to live a meaningful life.

Protagoras was the Sophist who was known for his argument that "beauty is in the eye of the beholder." This argument states that there is no objective standard of beauty, but rather that beauty is relative to the individual.

Protagoras was the Sophist who was known for his argument that "truth is relative." This argument states that there is no objective truth, but rather that truth is relative to the individual.

Protagoras was the Sophist who was known for his argument that "the gods do not exist." This argument was considered to be very controversial at the time.