Platonism
Plato, following his teacher, Socrates (and, it is likely, the older tradition of Pythagoras), understands philosophy as philo-sophia, or, literally, the love of Wisdom. This understanding of philosophia permeates Plato's dialogues, especially the Republic. In that work, the leaders of the proposed utopia are to be philosopher kings: rulers who love sophia, Wisdom.
Sophia is one of the four cardinal virtues in Plato's Protagoras.
The Pythian Oracle (Oracle of Delphi) reportedly answered the question of "who is the wisest man of Greece?" with "Socrates!" Socrates defends this verdict in his Apology to the effect that he, at least, knows that he knows nothing. As is evident in Plato's portrayals of Socrates, this does not mean Socrates' wisdom was the same as knowing nothing; but rather that his skepticism towards his own self-made constructions of knowledge left him free to receive true Wisdom as a spontaneous insight or inspiration. This contrasted with the attitude of contemporaneous Greek Sophists, who claimed to be wise and offered to teach wisdom for pay.
Read more about this topic: Sophia (wisdom)