Further, since of all the supersensible absolutely nothing [is known] except freedom (through the moral law), and this only so far as it is inseparably implied in that law, and moreover all supersensible objects to which reason might lead us, following the guidance of that law, have still no reality for us, except for the purpose of that law, and for the use of mere practical reason; and as reason is authorized and even compelled to use physical nature (in its pure form as an object of the understanding) as the type of the judgement; hence, the present remark will serve to guard against reckoning amongst concepts themselves that which belongs only to the typic of concepts. This, namely, as a typic of the judgement, guards against the empiricism of practical reason, which founds the practical notions of good and evil merely on experienced consequences (so-called happiness). No doubt happiness and the infinite advantages which would result from a will determined by self-love, if this will at the same time erected itself into a universal law of nature, may certainly serve as a perfectly suitable type of the morally good, but it is not identical with it. The same typic guards also against the mysticism of practical reason, which turns what served only as a symbol into a schema, that is, proposes to provide for the moral concepts actual intuitions, which, however, are not sensible (intuitions of an invisible Kingdom of God), and thus plunges into the transcendent. What is befitting the use of the moral concepts is only the rationalism of the judgement, which takes from the sensible system of nature only what pure reason can also conceive of itself, that is, conformity to law, and transfers into the supersensible nothing but what can conversely be actually exhibited by actions in the world of sense according to the formal rule of a law of nature. However, the caution against empiricism of practical reason is much more important; for mysticism is quite reconcilable with the purity and sublimity of the moral law, and, besides, it is not very natural or agreeable to common habits of thought to strain one's imagination to supersensible intuitions; and hence the danger on this side is not so general. Empiricism, on the contrary, cuts up at the roots the morality of intentions (in which, and not in actions only, consists the high worth that men can and ought to give to themselves), and substitutes for duty something quite different, namely, an empirical interest, with which the inclinations generally are secretly leagued; and empiricism, moreover, being on this account allied with all the inclinations which (no matter what fashion they put on) degrade humanity when they are raised to the dignity of a supreme practical principle; and as these, nevertheless, are so favourable to everyone's feelings, it is for that reason much more dangerous than mysticism, which can never constitute a lasting condition of any great number of persons. BOOK_1|CHAPTER_3