Plato’s third trip to Syracuse was motivated by concern for Dion’s life. Dionysius II sent messengers to Athens to request that Plato return to Syracuse. They reported that Dionysius II had made great progress in his philosophical studies, while Dionysius II himself wrote to Plato, promising that “no mercy would be shown to Dion unless Plato were persuaded to come to Sicily; but if he were persuaded, every mercy”. And so, Plato returned to Syracuse in 362, “that he might once more measure back his way to fell Charybdis”. Unfortunately, like his first two trips, Plato’s third trip to Syracuse quickly became embroiled in court intrigue and ended in failure. He eventually returned to Athens and reported on his travels to Dion while attending the Olympics of 360. The message was clear: Dionysius II was incorrigible and dangerous.
Dion immediately began plotting to invade Syracuse and seek revenge against Dionysius II, who had taken his money and land, and married his wife to another man while he was banished from Syracuse. He felt compelled to attack in retaliation. In 357, with the help of Speusippus and several other members of Plato’s Academy—though not Plato because of his age and his firm stance against vengeance —Dion landed in Syracuse and succeeded in conquering the city while Dionysius II was away on his own military campaign in Italy. Dion’s grip on power in Syracuse did not last long, however. He quickly found himself in a conflict with a populist leader named Heracleides, who took advantage of the Syracusans’ distrust of Dion. Over the next two years, Dion was driven into exile for a second time, and then recalled back to Syracuse when, to the horror of most Syracusans, Dionysius II and his soldiers attempted to regain power in 355.
After an unusually destructive battle in the city, Dion succeeded in defeating Dionysius II for a second time, and in doing so he endeared himself to the Syracusans as never before. However, thanks to continued factionalism in Syracuse and the imperiousness of Dion’s rule, Dion’s supporters quickly abandoned him, and he was assassinated by Callipus, a member of Plato’s Academy. Syracuse was “continually exchanging one tyrant for another”. This was when Dion’s remaining followers fled to Leontini and wrote to Plato for his political advice. The Seventh Letter written in 353 BC is Plato’s response.
From: Plato at Syracuse: Essays on Plato in Western Greece with a new translation of the Seventh Letter
by Jonah Radding, edited by Heather Reid and Mark Ralkowski (Sioux City: Parnassos Press, 2019).