He comes to the conclusion that the harm done by involuntary circumcision must be weighed against its “contributions to the meanings of particular African…identities.” Appiah spends pages analyzing the alternatives and justifying his own notion of cosmopolitanism through the lens of the liberal philosophical tradition. He makes philosophical sense out of common sense, bending and plying theories of great thinkers of the past and present to assemble a comprehensive assessment of the meaning of identity.

Appiah weaves extensive quotations and citations of philosophers from Socrates to Bass Professor of Government Michael J. Sandel (to whom he respectfully refers, on first reference, as simply “Sandel”) into his very readable and occasionally colloquial prose—dotted with words that go untransliterated and untranslated.

This direct approach to philosophy brought to mind Appiah’s most persuasive defense of his profession. He likened the process of reading and developing philosophy to admiring a great painting in a museum—its real claim to your attention is not its history or the greatness of its creator, but simply that very act, the “engagement,” of looking at it.

“The intellectual worth of cultural productivity is worth studying,” Appiah said, “and it’s worth studying in itself, not because of what it does for our mind or even that it teaches us about reality, but because interacting with works of great achievement is valuable.”

And in The Ethics of Identity, Appiah does even more than celebrate the achievements of the liberal intellectual tradition. He adds one more.

--Staff writer Anton S. Troianovski can be reached at atroian@fas.harvard.edu.