The originality of Heidegger’s philosophy lies in the unique nature of his understanding of Being. First of all, it must be said that the philosopher thinks of Being historically and not categorically. Heidegger points out that neither Being nor Time is something that exists. Being takes place in being through the admission of presence, that is, the opening of the secret. Time, however, should not be understood as a specific duration, or a consecutive series of moments, or the alternation of these moments. Time shows itself as time, looking into being in the sense of the present.
The philosopher considers phenomenology as a method of ontology, the teaching of Being about existence. Heidegger speaks of the phenomenology of human existence or Dasein, which brings about “worlds.” A human being or existence is such that it understands its Being and simultaneously the Being of other entities around them. Heidegger’s purpose in Being and Time is to describe how human Being deals with their meanings.
Dasein is the innermost ability in a person that understands being in general; it is the part of consciousness that asks the question of existence and knows about the fragility of its Being, about death, which opens people to their place in the universe. Heidegger emphasizes that one should not confuse the concept of Dasein with the subject: Dasein objectively exists – it is a being.