Reason and Existenz
Written during the rise of German National Socialism, Jaspers' Reason and Existenz attempts to systematize existentialist philososphy. Unlike Sarte's notion that the future holds infinite choice, Jaspers argues (in agreement with his colleague Heidegger) that the future is a mere rehash of the past where every action has already been anticipated. Thus, for Jaspers only what has already been done in the past can be done in the present and into the future.
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