There are good reasons for Iris Murdoch to try her hand at writing philosophical dialogues. She is, after all, a retired Oxford philosophy tutor and the author of a dozen or so studies in ethics and aesthetics (as well as an early monograph on Sartre) that are highly regarded by the post-Fach crowd, who wish philosophy were less like science and more like poetry. And she has long appreciated the advantages of this classic form: in her first published novel, Under the Net (1954), she had the protagonist deflate the systematizing pretensions of a professional philosopher by writing a dialogue called “The Silencer” (those were the days of Wittgenstein, remember).

Among the genres available to philosophers, there is something uniquely forthright about the dialogue. It seems truly to mirror the process of philosophical discovery. Paul Valéry somewhere remarked that it takes two to invent anything: one to generate, one to select—and discard. According to this view, when a single person is doing the inventing, what is really going on is a sort of cognitive trafficking among homunculi in the head—what the Stranger in the Sophist called “the inward dialogue.” Socrates submits in the Theaetetus that the act of judgment occurs when the interior voices finally affirm the same thing.

So it is natural that philosophers should be drawn to the dialogue. For Murdoch, however, it has a special allure: as a Booker Prize-winning author of twenty-two novels and a few odd plays and poems, she is