[231] On Jacobi, see Tennemann's _Manual of the History of Philosophy_, vol. iii., p. 318, etc. [232] On this important question of method, see lecture 12. LECTURE XV. PRIVATE AND PUBLIC ETHICS. Application of the preceding principles.--General formula of interest,--to obey reason.--Rule for judging whether an action is or is not conformed to reason,--to elevate the motive of this action into a maxim of universal legislation.--Individual ethics. It is not towards the individual, but towards the moral person that one is obligated. Principle of all individual duties,--to respect and develop the moral person.--Social ethics,--duties of justice and duties of charity.--Civil society. Government. Law. The right to punish. We know that there is moral good and that there is moral evil: we know that this distinction between good and evil engenders an obligation, a law, duty; but we do not yet know what our duties are. The general principle of ethics is laid down; it must be followed at least into its most important applications. If duty is only truth become obligatory, and if truth is known only by reason, to obey the law of duty, is to obey reason. But to obey reason is a precept very vague and very abstract:--how can we be sure that our action is conformed or is not conformed to reason? The character of reason being, as we have said, its universality, action, in order to be conformed to reason, must possess something universal; and as it is the motive itself of the action that gives it its morality, it is also the motive that must, if the action is good, reflect the character of reason. By what sign, then, do you recognize that an action is conformed to reason, that it is good? By the sign that the motive of this action being generalized, appears to you a maxim of universal legislation, which reason imposes upon all intelligent and free beings. If you are not able thus to generalize the motive of an action, and if it is the opposite motive that appears to you a universal maxim, your action, being opposed to this maxim, is thereby proved to be contrary to reason and duty,--it is bad. If neither the motive of your action nor the motive of the opposite action can be erected into a universal law, the action is neither good nor bad, it is indifferent. Such is the ingenious measure that Kant has applied to the morality of actions. It makes known with the last degree of clearness where duty is and where it is not, as the severe and naked form of syllogism, being applied to reasoning, brings out in the precisest manner its error or its truth. To obey reason,--such is duty in itself, the duty superior to all other duties, giving to all others their foundation, and being itself founded only on the essential relation between liberty and reason.