If the notion of good is not to be derived from an antecedent practical law, but, on the contrary, is to serve as its foundation, it can only be the notion of something whose existence promises pleasure, and thus determines the causality of the subject to produce it, that is to say, determines the faculty of desire. Now, since it is impossible to discern a priori what idea will be accompanied with pleasure and what with pain, it will depend on experience alone to find out what is primarily good or evil. The property of the subject, with reference to which alone this experiment can be made, is the feeling of pleasure and pain, a receptivity belonging to the internal sense; thus that only would be primarily good with which the sensation of pleasure is immediately connected, and that simply evil which immediately excites pain. Since, however, this is opposed even to the usage of language, which distinguishes the pleasant from the good, the unpleasant from the evil, and requires that good and evil shall always be judged by reason, and, therefore, by concepts which can be communicated to everyone, and not by mere sensation, which is limited to individual [subjects] and their susceptibility; and, since nevertheless, pleasure or pain cannot be connected with any idea of an object a priori, the philosopher who thought himself obliged to make a feeling of pleasure the foundation of his practical judgements would call that good which is a means to the pleasant, and evil, what is a cause of unpleasantness and pain; for the judgement on the relation of means to ends certainly belongs to reason. But, although reason is alone capable of discerning the connexion of means with their ends (so that the will might even be defined as the faculty of ends, since these are always determining principles of the desires), yet the practical maxims which would follow from the aforesaid principle of the good being merely a means, would never contain as the object of the will anything good in itself, but only something good for something; the good would always be merely the useful, and that for which it is useful must always lie outside the will, in sensation. Now if this as a pleasant sensation were to be distinguished from the notion of good, then there would be nothing primarily good at all, but the good would have to be sought only in the means to something else, namely, some pleasantness.