Thom Gunn's new book of poems [The Passages of Joy] comes clean with a companion volume of essays [The Occasion of Poetry], as if someone were trying to package him as an august poet and critic—the gay Matthew Arnold of his time. Even their titles have parallel ambiguities. What's an Occasion? What's a Passage?

As an essayist, Gunn is modest and generous, belying the hype. Some of his essays—like those of Rod Taylor, Dick Davis, and James Merrill—are "occasional" in that they're short, casual, slight, even fugitive, floating away into thin air on their own gracefulness. Yet the longer pieces on Fulke Greville and Thomas Hardy are "occasional" in a more satisfying sense: here Gunn unassumingly puts his intelligence wholly at the service of the occasioning subject, which is never a mere pretext for self-analysis or sermonizing. He's well worth reading when he explains how...