Protagoras is one of Plato’s earliest Socratic dialogues and was probably written around 385 BCE. It describes philosophy’s equivalent to a heavyweight boxing match: Socrates’s encounter with Protagoras, the most famous Sophist of Ancient Greece. Protagoras also gives us what is likely the best exposition of a central doctrine of Socratic philosophy, which is that virtue is knowledge, and evil is just another name for ignorance. This helps us understand the huge importance Socrates and Plato granted to the subject of education. If virtue is knowledge, then education (the instruction of youth) is, in a very real sense, the creation or destruction of virtuous souls. Protagoras is something of an anomaly among the dialogues in that it is set before Plato’s own birth at a period in which Socrates is still a young man.


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