Philosophic Classics From Plato to Derrida

894 IMMANUELKANT

universal realm of ends regarded as they are in themselves (rational beings) can awaken in

us a lively interest in the moral law. To that realm we can belong as members only when we

scrupulously conduct ourselves by maxims of freedom as if they were laws of nature.

Concluding Remark

The speculative use of reason with respect to nature leads to the absolute necessity

of some supreme cause of the world. The practical use of reason with respect to freedom

leads also to an absolute necessity, but to the necessity only of laws of actions of a rational

being as such. Now it is an essential principle of all use of reason to push its knowledge to

an awareness of its necessity, for otherwise it would not be rational knowledge. But it is

also an equally essential restriction of this very same reason that it cannot discern the

necessity of what is or of what occurs or of what ought to be done unless a condition

under which it is or occurs or ought to be done is presupposed. In this way, however, the

satisfaction of reason is only postponed further and further by the unceasing search for the

condition. Reason, therefore, restlessly seeking the unconditionally necessary, sees itself

compelled to assume it though it has no means by which to make it comprehensible; it is

happy enough if it can discover only the concept which is compatible with this presuppo-

sition. It is, therefore, no objection to our deduction of the supreme principle of morality,

but a reproach that we must make to human reason generally, that it cannot render com-

prehensible the absolute necessity of an unconditional practical law (such as the categori-

cal imperative must be). Reason cannot be blamed for being unwilling to explain it by a

condition (i.e., by making some interest its basis), for then the law would cease to be

moral and would no longer be the supreme law of freedom. And so we do not indeed com-

prehend the unconditional practical necessity of the moral imperative; yet we do compre-

hend its incomprehensibility, which is all that can fairly be demanded of a philosophy

which in its principles strives to reach the boundary of human reason.

ON A SUPPOSED RIGHT TO LIE FROM

ALTRUISTIC MOTIVES

In the journal Francefor 1797, Part VI, No. 1, page 123, in an article entitled “On

Political Reactions” by Benjamin Constant,* there appears the following passage:

The moral principle, “It is a duty to tell the truth,” would make any society impossible

if it were taken singly and unconditional!” We have proof of this in the very direct

consequences which a German philosopher has drawn from this principle. This

philosopher goes so far as to assert that it would be a crime to lie to a murderer who

asked whether our friend who is pursued by him had taken refuge in our house.

Critique of Pratical Reason and Other Writings in Moral Philosophy,translated by Lewis White Beck

(Chicago: University of Chicago Press, 1949). Reprinted by permission.

*Henri Benjamin Constant de Rebecque (1767–1830), the French writer, statesman, and orator.

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