Plato’s _Symposium_ contains two curious theories of the cause and origin of love, which, in conclusion, may be briefly summarised, as they help to characterise Greek notions on this subject. The first is placed in the mouth of Sokrates, who says he heard it of the Hetaira Diotima. What, she asks, is the cause of this love-sickness, this anxiety of men and animals, first to get a mate, and then to take care of the offspring? It is, she replies, the desire to perpetuate themselves. For just as the famous heroes and heroines—Alkestis, Achilles, Kadros—would not have so nobly sacrificed their lives had they not been sustained by the thought that their fame and glory would survive among future generations; so the fact that parents in the affection for their young will even go so far as to sacrifice their own lives to protect them, is due to their craving for immortality in their offspring. This theory may be regarded as a vague foreshadowing of Schopenhauer’s, which will be considered in another place. The second theory of the origin of love is attributed by Plato to Aristophanes, who relates it in the form of a myth. Human nature, he begins, was not always as it is now. At the beginning there were three sexes: one, the male, descended of the sun-god; the second, female, descended of the earth; and the third, which united the attributes of both sexes, descended of the moon. Each of these beings, moreover, had two pairs of hands and legs, and two faces, and the figure was round, and in rapid motion revolved like a wheel, the pairs of legs alternately touching the ground and describing an arc in the air. These beings were fierce, powerful, and vain, so they attempted to storm heaven and attack the gods. As Zeus did not wish to destroy them—since that would have deprived him of sacrifices and other forms of human devotion—he resolved to punish them by diminishing their strength. So he directed Apollo to cut each of them into two, which was done; and thus the number of human beings was doubled. Each of these half-beings now continually wandered about, seeking its other half. And when they found each other, their only desire was to be reunited by Vulcan and never be parted again. “And this longing and striving after union—this is what is meant by the name of Love.” The waggish Aristophanes appends a caution to human beings not to offend Zeus again, because it was that god’s intention, on a repetition of the offence, to split human beings once more, so that they would have to hop about on one leg!