Chapter 12

The ontological laws which govern practical reasonin general

1396. After discussing the principal ontological laws which govern the rational principle in its actions, I must now discuss those governing the actions of practical reason.
According to me, practical reason is something more than the kind of reason (speculative) which determines what may or may not be done, what may or may not be fitting. Practical reason is a rational , decision-making principle (223) governed by the ontological laws under discussion.

1397. These laws must be the same as those governing theoretical reason (that is, reason in its first acts) whose subsequent acts pertain to practical reason. If these laws are lacking, reason is lacking. Practical reason , however, is reason because there is only one rational principle which as knowing is 'theoretical', as acting 'practical'.(224) Obviously, therefore, the laws applicable to speculation are also applicable to decision-making because they have their source in the nature of a common principle. In a word, theoretical reason becomes practical when it acts. But because it acts as knower, the laws governing it as knower must be those which govern its activity.

1398. These laws are natural to reason, just as the laws of the communication of motion are natural to bodies. But here a difficulty presents itself. Sensitive nature and even purely sensible nature always obey their laws. Why then does reason infringe them by falling into error , which is a violation of the laws of theoretical reason, and by falling into sin , which is a violation of the laws of practical reason? The simple reply that reason, being free, can infringe the laws, does not solve the difficulty. It merely states the fact which seems to contradict the concept of the law. On the one hand, the difficulty requires the contradiction to be eliminated; we have to demonstrate the existence of truly natural laws which can nevertheless be violated. On the other hand, the character of natural law seems to require the impossibility of its violation.

The solution to the difficulty will be found if we note that foreign agents subject to laws different from those of reason are involved in the actions of the rational principle. Violation of the laws of reason arises therefore from the collision between various laws of different character. This also explains the wonderful fact of human freedom, which I have already discussed,(225) and to which I will return after explaining the supreme law of practical reason.

Notes

(223) Cf. PE , 1-14 and Conscience , 18-22.

(224) Cf. Teodicea , 161, concerning Kant's error: he made theoretical and practical reason two radically different faculties.

(225) Teodicea , 384-415.