In investigating the principles of moral conduct, then, the natural method is, to begin with the simplest ele ments of feeling : and then to proceed to the circum stances which occur in the constitution of our bodies, or in the powers of our minds, or in the order of external nature, to modify, limit, and restrain our appetites and feelings : and if this process is conducted judiciously, we shall probably find, that the Author of our nature has established immutable rules in the ordinations of his providence, to lead us to the high purposes for which we are destined.
If we shall succeed in establishing this point, it will prove incontrovertibly that there is nothing arbitrary or conventional in morals ; but that they result neces sarily from the powers and faculties which God has given to man, and from the circumstances in which he has placed him. Even the most exalted moral pre cepts, derived from the light of revelation, will be found not to controvert, but to confirm this position. It is a great mistake to suppose that Christianity un folds moral precepts foreign to the nature of man, and not cognizable by his reason. It is addressed to him as a perverted being, not as one destitute of the mate •ials of knowledge: it. shows that he neglects the riches which are among his hands, and that he fails to deduce the inferences which are obviously presented in his own nature, in the constitution of the external world, and in the ordinary events of providence. It is doing Christianity great injustice, to suppose that its moral precepts are such as never did or could enter the mind of man without it. Grotius takes up a very different argument to prove the divine origin of the Christian religion; for he endeavours to show that it was so rea sonable, and so admirably adapted to the nature and circumstances of man, that all its precepts might be recognized in the scattered maxims diffused among the human race ; but in all cases deformed by impure admixtures, and perverted from their original purpose by the vices and passions of men. The grand object of Christianity was, to unfold a plan of mercy, which must otherwise have remained unknown : its peculiarity, as a moral system, consists in the powerful sanctions by which its simple and obvious precepts are enforced. Instead, then, of being jealous of those moral maxims adopted, and beautifully illustrated, by many heathen authors, every Christian should consider them as so many attestations to the existence of that immutable law on which God has laid the foundation of morals. To deny the existence of such a law, would be to destroy at once the moral responsibility of man, where the light of revelation is unknown ; for cc where there is no law there is no transgression,"—an assertion which the apos tle makes, not to free the unenlightened heathen from responsibility, but to show their great guilt in neglect ing the clear intimations written on their hearts, and pointed out by the general constitution and course of nature. But unless such intimations existed, no blame could attach ; for who could be censured for invincible ignorance ? The law of moral action is in fact so irrevocably fixed, that even when we violate it unconsciously, we are cor rected, and called back to the consideration of the cir cumstances which have affected our comfort. Thus
temperance, one of the cardinal virtues, is forced on us by necessity ; and whenever we go beyond the limits prescribed by the constitution of our nature, we are in stantly punished, and taught to seek that just medium which may satisfy, but not satiate; and exhilarate, with out subverting by excessive excitement.
But although it is quite evident that the Author of our existence has put into our hands the inatei ials of knowledge, and directed us, by the constitution and circumstances of our nature, to the course of moral ac tion which we should pursue ; yet it is certain that we never could convert these materials to our advantage, without the aid of information superior to that afforded by the natural reason of man. All that we have hither to said amounts merely to this, that God has most abundantly furnished the means of information, with regard to the leading duties of morality : and we must now farther admit, that the materials of prejudice and error are no less abundantly supplied by toe tendency of our appetites and passions. It is this which renders human nature a strange medley of folly and of wisdom ; of virtuous feelings and depraved affections; which weakens the convictions even of the most enlightened, and teaches them to desire an authoritative rule and sanction, for the regulation or their conduct.—In short, the principles of natural morality stand pretty nearly on the same footing with the principles of natural reli gion : for though the being and attributes of God may be inferred from all his works, yet we sec that the natural reason of man never led him to just and accurate conceptions on the subject. In the same manner, though the rule of moral conduct may be traced in the order of nature, and in the constitution of our own minds, yet there can be no doubt that the light of re velation was necessary, to enable mankind to distin guish, with certainty, truth from error, and the illu sions of the passions from the rule of right reason. For who could decide with absolute certainty amidst the endless varieties of human opinions ; or expect to have the authority of an oracle in commanding the assent of mankind ? This difficulty was so powerfully felt by Socrates, that he deemed it necessary that an instructor should be sent from heaven with special authority to reveal and enforce the duty of man. Cicero did not go quite so far as this ; but his words evince no less clearly the necessity of such a teacher. He says, that he was not one of those who maintained that there was no such thing as absolute truth ; but that error was so mixed up with every truth, that it could not be accurately dis tinguished.* And to prove the truth of this observation, he adduces the discordant opinions of the principal phi losophical sects respecting the nature of the gods. If we are more fortunate than those two illustrious heathens, and can proceed with greater confidence in our investi gations, it is because we have been favoured with a re velation which was denied to them, and which has mate rially influenced the moral discussions even of those who reject its assistance.