Her subject in the book is ostensibly the role of eros--love or desire--in ancient Greek literature and philosophy. But there is not a clear thesis of the form "*Eros* plays such-and-such a role in so-and-so's poetry." Carson does not offer propositional knowledge.

Instead, the book is a sort of essay in the original sense of the French essayer, to try. Essays are attempts to grapple with an idea or concept, and they may or may not come to firm conclusions. Carson grapples with eros, aided by ancient writers acting as partners in dialogue. One gets the sense that Carson is not so much trying to convey what eros was to the Greeks, but what eros is.

What is eros, then? Eros is romantic love that is "bittersweet," as Sappho wrote. It is pleasurable because it is painful. We want it because we cannot have it. Eros is "the experience of melting." If two people are in love, eros is the gap between them. Eros is paradox and metaphor.

If all of this sounds hokey and ill-defined, well, it is. More rigid, analytic attempts to define romantic love would be even more unsatisfactory. But Carson treats the subject is such a way that--to borrow a literary cliche--you discover what you already know, which is the purest sort of knowledge.

Lyrical, erudite, and witty, Eros the Bittersweet defies summary. Like all that is best, it cannot be explained, only experienced. As I read it, I thought "there is something vitally important here." Maybe even important enough to learn Greek.