This chapter is guided by the following questions: What is first philosophy for Levinas? and Why can first philosophy be neither metaphysics nor ontology? I shall show why, given Levinas' characterization of the encounter of a subject with an other, it is not possible for first philosophy to be a deduction from, or an inquiry into, the possibility of being or knowledge. There is, nevertheless, an ontology in Levinas. In this chapter, I explore the meaning and limits of Levinas' ontology. The present chapter asks, moreover, what relation exists between what is and the "good', which for Levinas as for Plato, lies beyond being itself. Now, the question of a relation between being and transcendence opens a discussion of mediations. The most remarkable of these, for Levinas, is language.