Absolute reality thus is impossible in the world of Descartes. The way Kant began argument for his form of metaphysics began with the critique of pure reason. That involves the realm of the unknown -- moving to the unknown from the known, and this can be determined only by small steps. (Heidegger; Churchill, 9) Thus as per Kant "critique requires knowledge of the sources, and reason must know itself." And thus the pure reason may have to know first of itself. (Heidegger; Churchill, 133) Kant attempted to reach the origin of things by discarding the earlier metaphysics and relying on his own insight, with which he created the foundation of his analysis. As between them Kant leans more to the Greek forms and enhances the thought while Descartes would not have any of that. In the end both have succeeded in the emphasis of the thought that perceptions of these are still in the realms of abstract thought and there are many open ended questions for which we may never get an answer that is the absolute truth and end.

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