Reason is the discovery of truth or falsehood. Truth or falsehood consists in an agreement or disagreement either to the real relations of ideas, or to real existence and matter of fact. Whatever, therefore, is not susceptible of this agreement or disagreement, is incapable of being true or false, and can never be an object of our reason. Now it is evident our passions, volitions, and actions, are not susceptible of any such agreement or disagreement; being original facts and realities, complete in themselves, and implying no reference to other passions, volitions, and actions. It is impossible, therefore, they can be pronounced either true or false, and be either contrary or conformable to reason.
This argument is of double advantage to our present purpose. For it proves directly, that actions do not derive their merit from a conformity to reason, nor their blame from a contrariety to it; and it proves the same truth more indirectly, by showing us, that as reason can never immediately prevent or produce any action by contradicting or approving of it, it cannot be the source of moral good and evil, which are found to have that influence. Actions may be laudable or blameable; but they cannot be reasonable: Laudable or blameable, therefore, are not the same with reasonable or unreasonable. The merit and demerit of actions frequently contradict, and sometimes control our natural propensities. But reason has no such influence. Moral distinctions, therefore, are not the offspring of reason. Reason is wholly inactive, and can never be the source of so active a principle as conscience, or a sense of morals.
But perhaps it may be said, that though no will or action can be immediately contradictory to reason, yet we may find such a contradiction in some of the attendants of the action, that is, in its causes or effects. The action may cause a judgment, or may be obliquely caused by one, when the judgment concurs with a passion; and by an abusive way of speaking, which philosophy will scarce allow of, the same contrariety may, upon that account, be ascribed to the action. How far this truth or falsehood may be the source of morals, it will now be proper to consider.
It has been observed, that reason, in a strict and philosophical sense, can have influence on our conduct only after two ways: Either when it excites a passion by informing us of the existence of something which is a proper object of it; or when it discovers the connection of causes and effects, so as to afford us means of exerting any passion. These are the only kinds of judgment, which can accompany our actions, or can be said to produce them in any manner; and it must be allowed, that these judgments may often be false and erroneous. A person may be affected with passion, by supposing a pain or pleasure to lie in an object, which has no tendency to produce either of these sensations, or which produces the contrary to what is imagined. A person may also take false measures for the attaining his end, and may retard, by his foolish conduct, instead of forwarding the execution of any project. These false judgments may be thought to affect the passions and actions, which are connected with them, and may be said to render them unreasonable, in a figurative and improper way of speaking. But though this be acknowledged, it is easy to observe, that these errors are so far from being the source of all immorality, that they are commonly very innocent, and draw no manner of guilt upon the person who is so unfortunate as to fail into them. They extend not beyond a mistake of fact, which moralists have not generally supposed criminal, as being perfectly involuntary. I am more to be lamented than blamed, if I am mistaken with regard to the influence of objects in producing pain or pleasure, or if I know not the proper means of satisfying my desires. No one can ever regard such errors as a defect in my moral character. A fruit, for instance, that is really disagreeable, appears to me at a distance, and through mistake I fancy it to be pleasant and delicious. Here is one error. I choose certain means of reaching this fruit, which are not proper for my end. Here is a second error; nor is there any third one, which can ever possibly enter into our reasonings concerning actions. I ask, therefore, if a man, in this situation, and guilty of these two errors, is to be regarded as vicious and criminal, however unavoidable they might have been? Or if it be possible to imagine, that such errors are the sources of all immorality?
And here it may be proper to observe, that if moral distinctions be derived from the truth or falsehood of those judgments, they must take place wherever we form the judgments; nor will there be any difference, whether the question be concerning an apple or a kingdom, or whether the error be avoidable or unavoidable. For as the very essence of morality is supposed to consist in an agreement or disagreement to reason, the other circumstances are entirely arbitrary, and can never either bestow on any action the character of virtuous or vicious, or deprive it of that character. To which we may add, that this agreement or disagreement, not admitting of degrees, all virtues and vices would of course be equal.
Should it be pretended, that though a mistake of fact be not criminal, yet a mistake of right often is; and that this may be the source
