Ancient Greek philosophy was divided into three sciences: physics,ethics, and logic. This division is perfectly suitable to the natureof the thing; and the only improvement that can be made in it is toadd the principle on which it is based, so that we may both satisfyourselves of its completeness, and also be able to determine correctlythe necessary subdivisions.
All rational knowledge is either material or formal: the formerconsiders some object, the latter is concerned only with the form ofthe understanding and of the reason itself, and with the universallaws of thought in general without distinction of its objects.Formal philosophy is called logic. Material philosophy, however, hasto do with determinate objects and the laws to which they are subject,is again twofold; for these laws are either laws of nature or of freedom. The science of the former is physics, that of the latter, ethics; they are also called natural philosophy and moral philosophy, respectively.
Logic cannot have any empirical part; that is, a part in which theuniversal and necessary laws of thought should rest on grounds takenfrom experience; otherwise it would not be logic, i.e., a canon forthe understanding or the reason, valid for all thought, and capable ofdemonstration. Natural and moral philosophy, on the contrary, can eachhave their empirical part, since the former has to determine thelaws of nature as an object of experience; the latter the laws ofthe human will, so far as it is affected by nature: the former,however, being laws according to which everything does happen; (388) thelatter, laws according to which everything ought to happen. Ethics,however, must also consider the conditions under which what ought tohappen frequently does not.
We may call all philosophy empirical, so far as it is based ongrounds of experience: on the other band, that which delivers itsdoctrines from a priori principles alone we may call purephilosophy. When the latter is merely formal it is logic; if it isrestricted to definite objects of the understanding it is metaphysics.
In this way there arises the idea of a twofold metaphysic-- ametaphysic of nature and a metaphysic of morals. Physics will thushave an empirical and also a rational part. It is the same withEthics; but here the empirical part might have the special name ofpractical anthropology, the name morality being appropriated to therational part.
[Divisions of Philosophy]
All trades, arts, and handiworks have gained by division oflabour, namely, when, instead of one man doing everything, eachconfines himself to a certain kind of work distinct from others in thetreatment it requires, so as to be able to perform it with greaterfacility and in the greatest perfection. Where the different kindsof work are not distinguished and divided, where everyone is ajack-of-all-trades, there manufactures remain still in the greatestbarbarism. It might deserve to be considered whether pure philosophyin all its parts does not require a man specially devoted to it, andwhether it would not be better for the whole business of science ifthose who, to please the tastes of the public, are wont to blend therational and empirical elements together, mixed in all sorts ofproportions unknown to themselves, and who call themselves independentthinkers, giving the name of minute philosophers to those who applythemselves to the rational part only-- if these, I say, were warned notto carry on two employments together which differ widely in thetreatment they demand, for each of which perhaps a special talent isrequired, and the combination of which in one person only producesbunglers. But I only ask here whether the nature of science does notrequire that we should always carefully separate the empirical fromthe rational part, and prefix to Physics proper (or empirical physics)a metaphysic of nature, and to practical anthropology a metaphysicof morals, which must be carefully cleared of everything empirical, sothat we may know how much (389) can be accomplished by pure reason in bothcases, and from what sources it draws this its a priori teaching,and that whether the latter inquiry is conducted by all moralists(whose name is legion), or only by some who feel a calling thereto.
As my concern here is with moral philosophy, I limit the questionsuggested to this: Whether it is not of the utmost necessity toconstruct a pure thing which is only empirical and which belongs toanthropology [i.e., psychology and social sciences]? for that such a philosophy must be possible is evidentfrom the common idea of duty and of the moral laws. Everyone mustadmit that if a law is to have moral force, i.e., to be the basis ofan obligation, it must carry with it absolute necessity; that, forexample, the precept, "Thou shalt not lie," is not valid for menalone, as if other rational beings had no need to observe it; and sowith all the other moral laws properly so called; that, therefore, thebasis of obligation must not be sought in the nature of man, or in thecirc*mstances in the world in which he is placed, but a priorisimply in the conception of pure reason; and although any otherprecept which is founded on principles of mere experience may be incertain respects universal, yet in as far as it rests even in theleast degree on an empirical basis, perhaps only as to a motive,such a precept, while it may be a practical rule, can never becalled a moral law.
Thus not only are moral laws with their principles essentiallydistinguished from every other kind of practical knowledge in whichthere is anything empirical, but all moral philosophy rests whollyon its pure part. When applied to man, it does not borrow the leastthing from the knowledge of man himself (anthropology), but gives lawsa priori to him as a rational being. No doubt these laws require ajudgement sharpened by experience, in order on the one hand todistinguish in what cases they are applicable, and on the other toprocure for them access to the will of the man and effectual influenceon conduct; since man is acted on by so many inclinations that, thoughcapable of the idea of a practical pure reason, he is not so easilyable to make it effective in concreto in his life.
A metaphysic of morals is therefore indispensably necessary, notmerely for speculative reasons, in order to investigate the sources ofthe practical principles which are to be found a priori in our reason,but (390) also because morals themselves are liable to all sorts ofcorruption, as long as we are without that clue and supreme canon bywhich to estimate them correctly. For in order that an action shouldbe morally good, it is not enough that it conform to the moral law,but it must also be done for the sake of the law, otherwise thatconformity is only very contingent and uncertain; since a principlewhich is not moral, although it may now and then produce actionsconformable to the law, will also often produce actions whichcontradict it. Now it is only a pure philosophy that we can look forthe moral law in its purity and genuineness (and, in a practicalmatter, this is of the utmost consequence): we must, therefore,begin with pure philosophy (metaphysic), and without it there cannotbe any moral philosophy at all. That which mingles these pureprinciples with the empirical does not deserve the name ofphilosophy (for what distinguishes philosophy from common rationalknowledge is that it treats in separate sciences what the latteronly comprehends confusedly); much less does it deserve that ofmoral philosophy, since by this confusion it even spoils the purity ofmorals themselves, and counteract its own end.
Let it not be thought, however, that what is here demanded isalready extant in the propaedeutic prefixed by the celebrated Wolfto his moral philosophy, namely, his so-called general practicalphilosophy, and that, therefore, we have not to strike into anentirely new field. Just because it was to be a general practicalphilosophy, it has not taken into consideration a will of anyparticular kind -- say one which should be determined solely from apriori principles without any empirical motives, and which we mightcall a pure will, but volition in general, with all the actions andconditions which belong to it in this general signification. By thisit is distinguished from a metaphysic of morals, just as generallogic, which treats of the acts and canons of thought in general, isdistinguished from transcendental philosophy, which treats of theparticular acts and canons of pure thought, i.e., that whosecognitions are altogether a priori . For the metaphysic of morals hasto examine the idea and the principles of a possible pure will, andnot the acts and conditions of human volition generally, which for themost part are drawn from psychology. It is true that (
391) moral laws andduty are spoken of in the general moral philosophy (contrary indeed toall fitness). But this is no objection, for in this respect also theauthors of that science remain true to their idea of it; they do notdistinguish the motives which are prescribed as such by reason alonealtogether a priori , and which are properly moral, from theempirical motives which the understanding raises to generalconceptions merely by comparison of experiences; but, without noticingthe difference of their sources, and looking on them all ashom*ogeneous, they consider only their greater or less amount. It is inthis way they frame their notion of obligation, which, though anythingbut moral, is all that can be attained in a philosophy which passes nojudgement at all on the origin of all possible practical concepts,whether they are a priori , or only aposteriori.Intending to publish hereafter a metaphysic of morals, I issue inthe first instance these fundamental principles. Indeed there isproperly no other foundation for it than the critical examination of apure practical reason; just as that of metaphysics is the criticalexamination of the pure speculative reason, already published. Butin the first place the former is not so absolutely necessary as thelatter, because in moral concerns human reason can easily be broughtto a high degree of correctness and completeness, even in thecommonest understanding, while on the contrary in its theoretic butpure use it is wholly dialectical; and in the second place if thecritique of a pure practical reason is to be complete, it must bepossible at the same time to show its identity with the speculativereason in a common principle, for it can ultimately be only one andthe same reason which has to be distinguished merely in itsapplication. I could not, however, bring it to such completeness here,without introduci ng considerations of a wholly different kind, whichwould be perplexing to the reader. On this account I have adoptedthe title of Fundamental Principles of the Metaphysic of Moralsinstead of that of a Critical Examination of the pure practicalreason.
But in the third place, since a metaphysic of morals, in spite ofthe discouraging title, is yet capable of being presented in popularform, and one adapted to the common understanding, I find it useful toseparate from it this preliminary treatise on its fundamentalprinciples, in order that I may not hereafter have need to introducethese necessarily subtle discussions into a book of a more simplecharacter. (392)
The present treatise is, however, nothing more than theinvestigation and establishment of the supreme principle ofmorality, and this alone constitutes a study complete in itself andone which ought to be kept apart from every other moral investigation.No doubt my conclusions on this weighty question, which has hithertobeen very unsatisfactorily examined, would receive much light from theapplication of the same principle to the whole system, and would begreatly confirmed by the adequacy which it exhibits throughout; butI must forego this advantage, which indeed would be after all moregratifying than useful, since the easy applicability of a principleand its apparent adequacy give no very certain proof of its soundness,but rather inspire a certain partiality, which prevents us fromexamining and estimating it strictly in itself and without regard toconsequences.
I have adopted in this work the method which I think mostsuitable, proceeding analytically from common knowledge to thedetermination of its ultimate principle, and again descendingsynthetically from the examination of this principle and its sourcesto the common knowledge in which we find it employed. The divisionwill, therefore, to be as follows:
1. First Section -- Transition from the common rational knowledge ofmorality to the phillosophical.
2. Second Section -- Transition from popular moral philosophy to themetaphysic of morals.
3. Third Section -- Final step from the metaphysic of morals to the critique of the pure practical reason.
Commentary
- Kant's Aims
- analytic vs. synthetic
- a priori vs. a posteriori
