Heidegger announces in the introduction to Being and Time that the provisional aim of the work is the interpretation of time "as the possible horizon of any understanding of being whatsoever". The essence of time is sought in the basic structure of Dasein. Dasein exists in an ontical sense in as far as it is present. Secondly, Dasein's particular way of existing means that it is always related to its own being, which makes it also an ontological entity. Just as originally Dasein has an understanding of its own being, it has an understanding of the being of entities that do not have the character of Dasein. As such, Dasein "is' ontic-ontological.