Being and time

In 'Being and Time', Heidegger delves into the fundamental question of what it means to 'be'.

The book is divided into two main divisions: the first analyzes the existentials of Dasein, or 'being-in-the-world', while the second grounds these existentials in temporality.

Heidegger introduces key concepts such as 'Dasein', 'Being-with', and the three temporal ecstases (having-been, present, and to-come), emphasizing that Dasein's existence is essentially futural and characterized by its possibilities and projects.

The work challenges traditional philosophical notions of subject and object, instead positing that Dasein is inseparable from its world and historical context.