This period of Plato's mastership was broken only by two journeys to Sicily, both undertaken with political objects. Plato knew well that the perfect State, as depicted in his "Republic," was not capable of realization in the Greece of his own time. Nevertheless, he took his political philosophy very seriously. Though the perfect republic was an unattainable ideal, yet, he thought, any real reform of the State must at least proceed in the direction of that ideal. One of the essential principles of the "Republic" was that the rulers must also be philosophers. Not till philosopher and ruler were combined in one and the same person could the State be governed upon true principles. Now, in the year 368 B.C., Dionysius the Elder died, and Dionysius the younger became tyrant of Syracuse. Dionysius despatched an invitation to Plato to attend his court and give him the benefit of his advice. Here was an opportunity to experiment. Plato could train and educate a {169} philosopher-king. He accepted the invitation. But the expedition ended disastrously. Dionysius received him with enthusiasm, and interested himself in the philosophical discourses of his teacher. But he was young, impetuous, hot-headed, and without genuine philosophic bent. His first interest gave place to weariness and irritation. Plato left Syracuse a disappointed man; and returned to Athens. Nevertheless, after the lapse of a few years, Dionysius again invited him to Syracuse, and again he accepted the invitation. But the second journey ended in disaster like the first, and Plato was even in danger of his life, but was rescued by the intervention of the Pythagoreans. He returned to Athens in his seventieth year, and lived till his death in the seclusion of his school, never again attempting to intervene in practical politics. For more than another decade he dwelt and taught in Athens. His life was serene, quiet, and happy. He died peacefully at the age of eighty-two. Plato's writings take the form of dialogues. In the majority of these, the chief part is taken by Socrates, into whose mouth Plato puts the exposition of his own philosophy. In a few, as for example the "Parmenides," other speakers enunciate the Platonic teaching, but even in these Socrates always plays an important _rôle_. Plato was not only a philosopher, but a consummate literary artist. The dialogues are genuinely dramatic, enlivened by incident, humour, and life-like characterization. Not only is the portrait of Socrates drawn with loving affection, but even the minor characters are flesh and blood.