PLATO: Protagoras - FULL AudioBook | Greatest AudioBooks Philosophy & Philosophers

PLATO: Protagoras - FULL AudioBook | Greatest AudioBooks Philosophy & Philosophers - Protagoras (Greek: Πρωταγόρας, ca. 490 BC -- 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 or teacher of virtue. He is also believed to have created a major controversy during ancient times through his statement that "man is the measure of all things". This idea was revolutionary for the time and contrasted with other philosophical doctrines that claimed the universe was based on something objective, outside the human influence.
Plato ascribes relativism to Protagoras and uses his predecessor's teachings as a foil for his own commitment to objective and transcendent realities and values particularly those that relate to his aristocratic background. His major effort, through the words of Socrates, is to convince his contemporaries that ἀρετή (aretē, virtue) is a present from the gods, which one either has or has not and that no sophist can teach virtue to people that do not already possess it. Plato ascribes to Protagoras an early form of phenomenalism, in which what is or appears for a single individual is true or real for that individual. However, as it is clearly presented in the Theaetetus, Protagoras explains that some of such controversial views may result from an ill body or mind. He stresses that although all views may appear equally true, and perhaps should be equally respected, they are certainly not of equal gravity. One may be useful and advantageous to the person that has it while another may prove harmful. Hence, the sophist is there to teach the student how to discriminate between them, i.e. to teach virtue.
Protagoras was a proponent of agnosticism. In his lost work, On the Gods, he wrote: "Concerning the gods, I have no means of knowing whether they exist or not or of what sort they may be, because of the obscurity of the subject, and the brevity of human life." (Summary from wiki)