To a great degree, Levinas's philosophical commitment to the primacy of ethics is a response to intellectual and historical challenges to morality in the nineteenth and twentieth centuries. Viewed in this way, Levinas's thought is a contribution to moral philosophy. Examining it, one can ask what he says about the grounds of moral obligation and value, the nature of morality, its normative content, and such. But we have seen that to read Levinas in this way is too narrow. It is more appropriate to take his philosophy as a contribution to understanding human existence in the broadest sense. It is, in this way, a philosophical anthropology or a philosophy of human existence, and Levinas's central teaching is that ethical matters are fundamental or central to human existence. He is not, of course, the first person to make this claim, but the way in which he argues for this position is distinctive. He claims that as human beings we are social beings, that is, that we have direct, first-person/second-person, face-to-face relationships with others, and that as social beings our relationships have an ethical character that is the most determinative feature of our existence with others in the world. This is at least part of what he means by the claim that “ethics is first philosophy.”

In traditional forms of Western philosophy, metaphysics or theology identified the most fundamental entities or principles on which all of reality is founded.