The moral theory of Immanuel Kant is based on his concept of the good will. For Kant, moral knowledge is a prior, or existing before and in spite of the fact. That is, there are moral precepts which determine how men ought to behave, and these precepts do not depend on actual behavior. Instead, there are truths, moral precepts, which are to be applied to all behavior. We might say that we ought to tell the truth, for instance, and this tells us how to behave. Even if we all tell lies, though, this does not change the fact that we ought to tell the truth, so the precept does not depend on our behavior. We need not even be aware of the moral precept for it to be valid and applicable. Our moral knowledge and the moral precepts we seek to understand have their origin in the practical reason, which is reason in its practical, or moral, function.
The notion of the good will is explained by Kant in "Metaphysical Foundations of Morals" where he writes: "Nothing can possibly be conceived in the world, or even out of it, which can be called good without qualification, except a good will" (Kant: p. 140). What Kant feels has to be explained is the meaning of the term "good" when applied to the will, and to accomplish this Kant uses the concept of duty, the most important element for Kant in his conception of the moral consciousness. Kant distinguishes between acts that are performed out of duty and acts which are performed for the sake of duty, stating that those acts performed in accordance with duty but not from duty have no moral worth. In making this distinction, Kant sets out a moral principle in keeping with his view that morality does not derive from nature but from the mind. What is important in moral terms is what is intended and not necessarily what actually occurs. An event occurring without intent is less valuable than an event occurring with intent. In two separate instances, the act might be precisely the same, but t...