There are several terms in Lévinas’ philosophy, to which his reader better should not assign traditional meanings. The paper focuses on Lévinas’ usage of the terms “ontology” and “metaphysics”, which reveal the philosopher’s attempt to find their new interpretations. In his perspective, both terms become synonyms of the key concepts of his philosophy. In the context of Lévinas’ criticism of Western philosophical tradition, “ontology” refers to totalization, i.e. a philosophy aiming at a unity, but at the same time denying the alterity of the Other. “Metaphysics”, on the other hand, expresses transcendence leading to plurality and cherishing the otherness. Lévinas finds its formal structure in Descartes’ idea of the infinity in us and its tangible expression in the ethical attitude towards the Other. Consequently, the term “first philosophy” should be attributed to ethics, not as a normative and casuistic discipline, but as a relation to the Other in his otherness, which the philosophy as the “love for wisdom” transforms into the “wisdom of love”.