It is true that for human being to become Da-sein, it has to recognize its personal possible non-existence, and then recognize the fact that beyond that non-existence a residual lucidity about being remains. Da—sein is therefore that residual openness onto both nothingness, and also onto the world. This duality of facing life and death is called, in Heidegger’s work, a 'turning in enowning’. Da-sein must face both be-ing (nothing) and beings in the world.
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