Theseus

Hellanicus, however, says that the city did not send its young men and maidens by lot, but that Minos himself used to come and pick them out, and that he now pitched upon Theseus first of all, following the terms agreed upon. And he says the agreement was that the Athenians should furnish the ship, and that the youths should embark and sail with him carrying no warlike weapon, and that if the Minotaur was killed the penalty should cease.

On the two former occasions, then, no hope of safety was entertained, and therefore they sent the ship with a black sail, convinced that their youth were going to certain destruction; but now Theseus encouraged his father and loudly boasted that he would master the Minotaur, so that he gave the pilot another sail, a white one, ordering him, if he returned with Theseus safe, to hoist the white sail, but otherwise to sail with the black one, and so indicate the affliction.