Complex sentence: He would have been known among the educated of the audience for his presence at the Greek banquet in Plato's Symposium at which he gets the last word on the nature of love, proposing that it cannot be found in superficial appearance.
Split into simpler sentences: He would have been known to those highly educated amongst the audience for his presence in the Greek banquet in Plato's Symposium. Here, he gets the last word on the nature of love, proposing that it cannot be found in superficial appearance.