To Hume, the concept of morality was not a universal concept, but a human construct founded on reason and human sentiment. The fact that individuals dispute whether an action is right or wrong and use a rational form of discussion to reach a conclusion is strong proof in favor of morality being founded on reason. However, humans also have feelings of approval or disapproval concerning these actions, which provides evidence that sentiment is also part of the human condition. Hume considers several opposing sentiments, such as pride and humility, or love and hate, and treats the way these feelings operate on us as concrete examples of our behavior, not as generalized abstractions. Sentiments motivate us and often place us in a position where we must make a judgment, which is usually made by a coordination of reason and sentiment. Moral distinctions are thus not derived from reason but from our moral sense. What we regard as vice and virtue are not qualities in and of themselves, with an objective, independent existence, but qualities in our minds. Against the moral rationalists, who hold that moral judgments are based on reason, Hume maintains that it is difficult even to make their hypothesis intelligible. Reason, Hume argues, is a judgment about either matters of fact or relations. However, morality does not consist of a single matter of fact that can be immediately perceived, intuited, or grasped by reason alone, and therefore morality cannot be a judgment about matters of fact.
             The connection between reason and sentiment was, for Hume, the essence of morality. Hume held that a combination of the two was required to make moral judgments, for the reason that "Reason is, and ought only to be the slave of the passions, and can never pretend to any other office than to serve and obey them." Hume explains that reason alone can motivate nothing; reason can either determine matters of fact or establish the relations of ideas, and it dep...