Being-in-itself

Being-in-itself is the self-contained and fully realized Being of objects. It is a term used in early 20th century continental philosophy, especially in the works of Martin Heidegger, Jean-Paul Sartre, Simone de Beauvoir, and the existentialists.

In the philosophy of Martin Heidegger, Being-in-itself is contrasted with the being of persons, which he terms Dasein. (Heidegger 1962, p. H.27) "Dasein means: care of the Being of beings as such that is ecstatically disclosed in care, not only of human Being...Dasein is itself by virtue of its essential relation to Being in general." (Heidegger 2000, p. H.31) Fortunately, Heidegger recognized the dangers inherent to talking about Being in general and particular beings, and thus devoted space in Being and Time and the Introduction to Metaphysics to an explication of the differences; often noted by translators who distinguish Being (Sein), from a being (das Seiende). His attention to the complication is helpful for those who are looking for detailed explanation, but rarely clears the air of confusions.

Dasein is Being that is aware of, and interested in, its own Being. Dasein is, by its nature, invested in social interaction and society. This is because in Heidegger's metaphysical system, one of the most fundamental ways to understand Being is through relationships. All things stand in a relation to all other things — and by virtue of his stress on Dasein's ontological distinction, things may also stand in relation to Dasein. (Heidegger 1962, p. H.78) The argument for this claim draws heavily on Hegel's great work, the Phenomenology of Spirit. Essentially, Being in itself is one of Heidegger's main concerns throughout his authorship. Despite Heidegger's interest in it, he returns — more often than not indirectly — to the subject by interrogating other concepts that simply invoke Being without explicitly acknowledging it.

In other words, whereas Heidegger calls the being of persons 'Dasein', he determines 'Being in itself' to be at the same time the most vague and general concept possible to contemplate, but also the topic of greatest interest to him as a philosopher.

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