Being and Time (German: Sein und Zeit) is a 1927 book by the German philosopher Martin Heidegger, in which the author seeks to analyse the concept of Being. Heidegger maintains that this has fundamental importance for philosophy and that, since the time of the Ancient Greeks, philosophy has avoided the question, turning instead to the analysis of particular beings. Heidegger attempts to create a more fundamental ontology through understanding being itself. He approaches this through seeking understanding of beings to whom the question of being is important, i.e. Dasein, or the human being in the abstract.
Heidegger wrote that Being and Time was made possible by his study of Edmund Husserl’s Logical Investigations (1900-1901), and it is dedicated to Husserl “in friendship and admiration”. Although Heidegger did not complete the project outlined in the introduction, Being and Time remains his most important work. It was immediately recognized as an original and groundbreaking philosophical work, and later became a focus of debates and controversy, and a profound influence on 20th-century philosophy, particularly existentialism, hermeneutics, deconstruction, and the enactivist approach to cognition. Being and Time has been described as the most influential version of existential philosophy, and Heidegger’s achievements in the work have been compared to those of Immanuel Kant in the Critique of Pure Reason (1781) and Georg Wilhelm Friedrich Hegel in The Phenomenology of Spirit (1807) and Science of Logic (1812-1816). Jean-Paul Sartre wrote Being and Nothingness (1943) under the influence of Heidegger.