Why the person needs to learn itself?

In the ancient time on Apollo's temple in Delphi saying was traced: "Learn itself". Was considered that saying it was transferred from Ancient Greek god Zeus to the son Apollo who, according to myths, and founded this temple. And the oracle of the Delphic temple, in turn, foretold the truth transferred from gods to people. The philosopher Socrates after visit of the Delphic temple took this saying as a basis of the philosophical knowledge. He addressed to studying of a place of the person in the world, having moved it, according to Cicero, from heavens to the earth. Passed many years since then. However attitude of the person towards the...