Levinas sought to restore a new sense of an unconditional ethical imperative that could not be dismissed as merely abstract, formal, ahistorical, inauthentic, and ontologically inadequate. He did this by developing a phenomenology of the moral imperative that was derived not from the fact of Reason but from the face of the Other. (p. xix)Against Heidegger and much of twentieth-century philosophy, Levinas was firmly convinced, as Fagenblat puts it (p. 14), that ethical judgment is exercised over history and not simply within history.
The problem is that for Levinas, the face of the Other is completely transcendent and thus cannot be captured by description, explanation, or narration. As Fagenblat rightly observes (p. xx), it can only be respected or desired, loved or hated. That is why Levinas thinks ethics is first philosophy: it is the source of all meaning and intelligibility and cannot be derived from anything more basic. I will postpone the question of what type of ethics this approach produces until later. For the present, the important point is that, according to Fagenblat, Levinas reaches this conclusion not by conducting an exercise in pure phenomenology but by drawing on sources from Jewish tradition. What results is in fact "a coherent philosophy of Judaism" (p. xxii).