 This entry will follow Levinas’ career chronologically, as his concepts evolve. In what follows, we will emphasize the following arguments and themes: (1) why Levinas’ is a unique first philosophy; (2) how he developed his investigation of the lived conditions of possibility of our concern with ethical reasoning; and (3) the originality of his adaptation of phenomenology and his existentialist hermeneutics of pre-intentional embodied intersubjectivity. In this entry, attention is focused throughout to the contribution of commentators, with a view to providing a gateway to recent secondary literature.