Dasein is a German wor famously used by Martin Heidegger in his magnum opus Being and Time. The word Dasein was used by several philosophers before Heidegger, with the meaning of "existence" or "presence". It is derived from da-sein, which literally means being-there/here, though Heidegger was adamant that this was an inappropriate translation of Dasein. In German, Dasein is synonymous with existence, as in I am pleased with my existence (ich bin mit meinem Dasein zufrieden). For Heidegger, however, it must not be mistaken for a subject, that is something objectively present. Rather it is comparable to the earlier separation of "Subject" from "subject" in the immanentist philosophy of Giovanni Gentile. Heidegger was adamant about this distinction, which carried on Nietzsche's critique of the subject. Dasein, as a being that is constituted by its temporality, illuminates and interprets the meaning of Being in Time. For more information, see other related Heideggerian concepts, such as being-in-the-world.