Ancient sources describe him as a bright though modest boy who excelled in his studies. Apuleius informs us that Speusippus praised Plato's quickness of mind and modesty as a boy, and the "first fruits of his youth infused with hard work and love of study". His father contributed all which was necessary to give to his son a good education, and, therefore, Plato must have been instructed in grammar, music, and gymnastics by the most distinguished teachers of his time.• </ref> Plato invokes Damon many times in the "Republic". Plato was a wrestler, and Dicaearchus went so far as to say that Plato wrestled at the Isthmian games. Plato had also attended courses of philosophy; before meeting Socrates, he first became acquainted with Cratylus and the Heraclitean doctrines.