Rationalism and Reason For Its Own Sake

The foundation of any Rationalist Psychology or Rationalist Ethics is the possibility of Reason for its own sake as a motive of behavior.  For, otherwise, Reason can be only Instrumental, and, hence, only at the service of non-Rational principles, e. g. the Passions.  So, the primary task of a Rationalist is to ground that possibility.  One prominent example of that effort is Aristotle, who ascribes to humans a natural Teleology, which motivates them to fulfill their Rational potential.  Another is Spinoza, according to whom Reason is an immanent force that is obscured by external forces.  Now, Kant, influenced by Leibniz, proposes a variation on these two--that the fundamental principle of Reason is a principle of Practical Sufficient Reason, which governs any use of Reason.  One expression of the principle is the requirement that use of Reason in Maxim-formation is subject to the criterion of Universality.  However, the concrete experience of the Rational principle is the moment when one chooses Reason for its own sake, when one chooses for its own sake to follow the prescribed use of Reason for Maxim-formation.  Accordingly, Sufficiency is the fundamental value of Reason.  However, as has been previously discussed, Kant's primary ambition for a Rationalist doctrine is its adaptability to Theologically-based Deontic Morality.  Entailed in that adaptability is a shift of emphasis to Totality as the fundamental value of Reason, e. g. when he attributes to Reason, on the basis of Totality, the thesis that Virtue is incomplete without Happiness, the completion of which requires a rewarding deity.  The historical consequences of this shift of emphasis have been plain--the ascendance in the Rationalist tradition of Totalitarian Reason, e. g. Fichte, Schelling, and Hegel, and the marginalization of Sufficient Reason, e. g. the Pragmatists.  And, in the process, the motive of Reason for its own sake gets replaced by that of obedience to Duty for Duty's sake.