Eros

In Plato's Symposium, a series of speakers praise Eros at a drinking party, until Socrates reports the teaching of the priestess Diotima. Eros, she says, is not a god but a great daimon, child of Plenty and Poverty, forever in between — neither rich nor poor, neither wise nor ignorant — a longing that springs from lack and reaches toward what it lacks. Its true object is beauty, and through beauty, a kind of immortality.

The ladder of love

Diotima describes an ascent. The lover begins drawn to one beautiful body, then comes to see that the beauty of all bodies is one and the same, then rises to the beauty of souls, of laws and institutions, and of the sciences, and at last, suddenly, beholds Beauty itself — eternal, changeless, neither growing nor fading, the very Form of the beautiful, of which all beautiful things partake. This vision is the goal toward which love, rightly directed, has been climbing all along.

The afterlife of the idea

The Neoplatonists made this ascent central to the soul's return, and Plotinus wrote movingly of the love that draws the soul toward the Good. In the Renaissance Ficino named it 'Platonic love' — desire for bodily beauty transfigured into a spiritual movement toward the divine — a phrase that has lived on, somewhat flattened, ever since. Eros, in this tradition, is the very engine of ascent.