Kant: Political Writings

However exalted we may wish our concepts to be, and however abstract we may make them in relation to the realm of the senses, they will continue to be associated with figurative notions. The proper function of these is to make such concepts, which are not in other respects derived from experience, suitable for use in the experiential world. For how else could we endow our concepts with sense and significance if we did not attach them to some intuition (which must ultimately always be an example derived from some possible experience)? If we then subtract the figurative associations from this concrete act of the understanding— first those of fortuitous sense-perception, and then the pure sensuous intuition itself—we are left with the pure concept of the understanding, but with its scope now enlarged so as to constitute a complete rule of thought. This is the way in which even universal logic came into being; and in the application of our understanding and reason to experience, there may still lie hidden certain heuristic methods of thought which, if we could carefully extract them from experience, might well enrich philosophy with useful maxims, even in abstract thought.

To this category belongs that principle to which the late Moses Mendelssohn expressly declared his allegiance—but only, so far as I know, in his last writings (see his Morgenstunden ﹛Morning Hours), pp. 164f. and his letter An die Freunde Lessings (To Lessing's Friends), pp. 33 and 67): namely the maxim that it is necessary to orientate oneself in the speculative use of reason (which Mendelssohn, on other occasions, credited with considerable powers in the cognition of supra-sensory objects, and even with the power of conclusive proof) by means of a certain guideline which he sometimes described as common sense (in his Morgenstunden), sometimes as healthy reason, and sometimes as plain understanding (in An die Freunde Lessings). Who would have thought that this admission would not only have such disastrous effects on his favourable opinion of the power of speculative reasoning in theological matters (which was in fact inevitable), but also that even ordinary healthy reason, given the ambiguous position to which he relegated the use of this faculty in contrast to speculation, would risk becoming the basic principle of zealotry and of the complete subversion of reason?