Since ancient Greece the human being seeks the Truth of things outside himself, in the world and in its context of the world. In the twenty-first century, humanity is rescuing the teachings of Socrates, Plato, and Aristotle in search of self-knowledge. Is it possible to discern from the arguments of Gorgias (the sophist), who defended the impossibility of knowledge in a stable and definitive sense? "There is nothing that can be known; if it...