It is a violent transition from the sublimity of Socrates-Diotima to the drunken antics of Alcibiades, but the change is purely a change of tone; no change of subject is involved in Alcibiades' declaration that, if he is to follow the others and deliver a panegyric, the only possible subject for it is Socrates. Socrates is for Plato the perfect example of the lover of wisdom; Alcibiades calls him 'daemon-like', and it is hardly going too far to regard him as Eros incarnate; the most superficial reading reveals that in describing his character and way of life Plato is simply clothing in flesh and blood the sketch of Eros at work in the soul of the true philosopher already drawn by Diotima. This suggests another and weightier reason than that given above for the introduction of Diotima into the dialogue; it would be a violation of dramatic tact to put directly into the mouth of Socrates praise of a type of character of which he is himself shortly to provide the complete illustration; it would come dangerously near involving him in a panegyric of himself. Yet Socrates, as the leading figure of the dialogue, must make the speech which is the pivot of the whole; hence the device of making that speech a reported conversation, and the emphasis laid throughout upon Socrates' position as pupil. Though he fulfils Plato's conception of the ideal he does so unconsciously, and in thus representing him Plato remains faithful to fundamental historical fact.
Socrates, like Eros, is full of contradictions; spiritual beauty is allied in him to physical ugliness, and the appearance of a Satyr conceals a wonderful self-control, which makes him utterly indifferent to pleasure, hardship, and danger. Alcibiades illustrates these characteristics by anecdotes of events in Socrates' life, such as his celebrated trance at Potidaea (to which his behaviour on the way to Agathon's party provides a parallel on a smaller scale) and his courage on the retreat from Delium. But the supreme example of his mastery of sensual appetites is his resistance to Alcibiades' attempt to seduce him. We are not to suppose that he is not tempted, but he sets aside Alcibiades' charms as being of less value than the moral and intellectual beauty after which he is striving, and in this he shows himself the noblest kind of lover, who has passed beyond the love of physical beauty though he is still sensible of its attractions.
So far all is straightforward, but there is a complementary aspect of the relations of Socrates with Alcibiades. Whereas on the physical plane Socrates is the lover and Alcibiades the beloved, even though Socrates refrains from any gratification of physical desire, on the spiritual plane the roles are reversed. Alcibiades finds its hard to explain the nature of the attraction which Socrates exercises over him, the effect of which is to make him feel dissatisfied with himself and ashamed of his present way of life, but in terms of Diotima's doctrine it is clear that what draws him to Socrates is beauty of soul. As the possessor of this, Socrates is the beloved, and Alcibiades is sufficiently highly gifted to be in love with him for this reason. He is not, however, prepared to abandon himself to the consequences of this feeling, which would involve a complete conversion from his career of dissipation and political ambition; he attempts to win Socrates' affection by the offer of his own physical charms — an endeavour, no doubt, to quiet his uneasy conscious by proving to himself that Socrates is no better than other people. When this fails, he is left in a state of mingled irritation and attraction. he cannot tear himself away from Socrates, but he continues to kick against the pricks, unfortunately both for him and for Socrates with a thoroughness which the very brilliance of his endowments makes all the more complete. The best commentary on such a situation is provided by Plato himself in the Republic (494), where, no doubt with Alcibiades in mind, he shows that it is the most promising natures which go most disastrously wrong if they succumb to the temptations offered by public life. Alcibiades' condition may in fact be excellently summed up in the famous words Video meliora proboque, deteriora sequor, and it seems odd that, faced with the example of his conscious rejection of the higher for the lower, both Socrates and Plato should have remained unshaken in their profound belief that all wrong-doing is the result of ignorance.
However that may be, it is not to be doubted that one object of the Symposium in general and of Alcibiades' speech in particular is to make plain that Socrates was in no way responsible for Alcibiades' betrayal of his country in the Peloponnesian War two years after the dramatic date of the dialogue. It had been one of the main charges against Socrates at his trial that he had corrupted several of the most prominent and talented young Athenians by his conversation, and led them to abandon traditional morality and embark upon courses subversive of the Athenian democracy. The fact that an act of oblivion made it necessary to veil all reference to this in general terms in no way diminished the strength of the prejudice against Socrates on this account. Among those of his associates who had proved enemies of the state none bore a heavier share of guilt than Alcibiades, and, as far as he is concerned, Plato supplements in the Symposium the defence of Socrates against the charge of 'corrupting the young' which he has already elaborated in the Apology and elsewhere. So too the anecdotes of Potidaea and Delium serve a double purpose, revealing Socrates as patriotic citizen as well as true philosopher; there is indeed no end to the implications which may be traced in almost every line of Alcibiades' apparently unmethodical and extempore effusion.
One final point remains. Although, as has been said, the views which Socrates expresses as the teaching of Diotima cannot be attributed to the historical Socrates, we need not hesitate to accept as a veracious portrait the picture presented to us by Alcibiades. The Symposium is a companion piece to the Phaedo ; it represents Socrates in life as the Phaedo represents him in the hour of death, and in both dialogues historical fact is accompanied by a philosophical theory which cannot have been held by Socrates himself. In this matter the Phaedo is likely to offend the sensibilities of a modern reader even more than the Symposium, because it may seem to violate the sanctity of the hero's last moments; but in considering both we have to remember that however far Plato travelled beyond his master he never ceased to regard his own system as having been implicit in the methods and conclusions of Socrates — who remained for him, as he is here represented, the pattern of what human nature can be at its highest, the true philosopher in love.