Fundamental Principals of the Metaphysic of Morals | Page 9

to extricate myself from a present
difficulty by means of this subterfuge, but it must be well considered whether there may
not hereafter spring from this lie much greater inconvenience than that from which I now
free myself, and as, with all my supposed cunning, the consequences cannot be so easily
foreseen but that credit once lost may be much more injurious to me than any mischief
which I seek to avoid at present, it should be considered whether it would not be more
prudent to act herein according to a universal maxim and to make it a habit to promise
nothing except with the intention of keeping it. But it is soon clear to me that such a
maxim will still only be based on the fear of consequences. Now it is a wholly different
thing to be truthful from duty and to be so from apprehension of injurious consequences.
In the first case, the very notion of the action already implies a law for me; in the second
case, I must first look about elsewhere to see what results may be combined with it which
would affect myself. For to deviate from the principle of duty is beyond all doubt wicked;
but to be unfaithful to my maxim of prudence may often be very advantageous to me,
although to abide by it is certainly safer. The shortest way, however, and an unerring one,
to discover the answer to this question whether a lying promise is consistent with duty, is
to ask myself, "Should I be content that my maxim (to extricate myself from difficulty by
a false promise) should hold good as a universal law, for myself as well as for others? and
should I be able to say to myself, "Every one may make a deceitful promise when he
finds himself in a difficulty from which he cannot otherwise extricate himself?" Then I
presently become aware that while I can will the lie, I can by no means will that lying
should be a universal law. For with such a law there would be no promises at all, since it
would be in vain to allege my intention in regard to my future actions to those who would
not believe this allegation, or if they over hastily did so would pay me back in my own
coin. Hence my maxim, as soon as it should be made a universal law, would necessarily
destroy itself.
I do not, therefore, need any far-reaching penetration to discern what I have to do in order
that my will may be morally good. Inexperienced in the course of the world, incapable of
being prepared for all its contingencies, I only ask myself: Canst thou also will that thy
maxim should be a universal law? If not, then it must be rejected, and that not because of

a disadvantage accruing from it to myself or even to others, but because it cannot enter as
a principle into a possible universal legislation, and reason extorts from me immediate
respect for such legislation. I do not indeed as yet discern on what this respect is based
(this the philosopher may inquire), but at least I understand this, that it is an estimation of
the worth which far outweighs all worth of what is recommended by inclination, and that
the necessity of acting from pure respect for the practical law is what constitutes duty, to
which every other motive must give place, because it is the condition of a will being good
in itself, and the worth of such a will is above everything.
Thus, then, without quitting the moral knowledge of common human reason, we have
arrived at its principle. And although, no doubt, common men do not conceive it in such
an abstract and universal form, yet they always have it really before their eyes and use it
as the standard of their decision. Here it would be easy to show how, with this compass in
hand, men are well able to distinguish, in every case that occurs, what is good, what bad,
conformably to duty or inconsistent with it, if, without in the least teaching them anything
new, we only, like Socrates, direct their attention to the principle they themselves employ;
and that, therefore, we do not need science and philosophy to know what we should do to
be honest and good, yea, even wise and virtuous. Indeed we might well have conjectured
beforehand that the knowledge of what every man is bound to do, and therefore also to
know, would be within the reach of every man, even the commonest. Here we cannot
forbear admiration when we see how great an advantage the practical judgement has over
the theoretical in the common understanding of men. In the latter, if common reason
ventures to