| We shall thus ascertain whether, from the point of view of its practical interest, reason may not be able to supply us with that which, on the speculative side, it wholly denies us. |
| The whole interest of reason, speculative as well as practical, is centred in the three following questions: |
| 1. WHAT CAN I KNOW? |
| 2. WHAT OUGHT I TO DO? |
| 3. WHAT MAY I HOPE? |
| The first question is purely speculative. |
| We have, as I flatter myself, exhausted all the replies of which it is susceptible, and have at last found the reply with which reason must content itself, and with which it ought to be content, so long as it pays no regard to the practical. |
| But from the two great ends to the attainment of which all these efforts of pure reason were in fact directed, we remain just as far removed as if we had consulted our ease and declined the task at the outset. |
| So far, then, as knowledge is concerned, thus much, at least, is established, that, in regard to those two problems, it lies beyond our reach. |
| The second question is purely practical. |
| As such it may indeed fall within the province of pure reason, but still it is not transcendental, but moral, and consequently cannot in itself form the subject of our criticism. |
| The third question; If I act as I ought to do, what may I then hope?--is at once practical and theoretical. |
| The practical forms a clue to the answer of the theoretical, and--in its highest form- speculative question. |
| For all hoping has happiness for its object and stands in precisely the same relation to the practical and the law of morality as knowing to the theoretical cognition of things and the law of nature. |
| The former arrives finally at the conclusion that something is (which determines the ultimate end), because something ought to take place; the latter, that something is (which operates as the highest cause), because something does take place. |
| Happiness is the satisfaction of all our desires; extensive, in regard to their multiplicity; intensive, in regard to their degree; and protensive, in regard to their duration. |
| The practical law based on the motive of happiness I term a pragmatical law (or prudential rule); but that law, assuming such to exist, which has no other motive than the worthiness of being happy, I term a moral or ethical law. |
| The first tells us what we have to do, if we wish to become possessed of happiness; the second dictates how we ought to act, in order to deserve happiness. |
| The first is based upon empirical principles; for it is only by experience that I can learn either what inclinations exist which desire satisfaction, or what are the natural means of satisfying them. |
| The second takes no account of our desires or the means of satisfying them, and regards only the freedom of a rational being, and the necessary conditions under which alone this freedom can harmonize with the distribution of happiness according to principles. |
| This second law may therefore rest upon mere ideas of pure reason, and may be cognized a priorI. I assume that there are pure moral laws which determine, entirely a priori (without regard to empirical motives, that is, to happiness), the conduct of a rational being, or in other words, to use which it makes of its freedom, and that these laws are absolutely imperative (not merely hypothetically, on the supposition of other empirical ends), and therefore in all respects necessary. |