David Hume maintains that moral distinctions are derived from feelings of pleasure and pain of a special kind, and not, as advocated by many Western philosophers since Socrates – from reason.
Working from the empiricist principle that the mind is essentially passive, Hume argues that reason alone can never prevent or produce any action or affect. But since morality refers to actions and affections, it cannot be based on reason.
In addition, reason can influence our conduct in two ways .
- First, reason can inform us of the existence of something that is the object of a passion, and thus excite it.
- Second, reason can deliberate on ways to an end that we already desire.
But if the reason is wrong in any of these areas (for example, by confusing an unpleasant object with something pleasant or by wrongly choosing the wrong means for a desired end), it is not a moral failure, but an intellectual failure. As a final point, Hume defends a distinction between facts and values .
According to Hume, one cannot infer conclusions about what should or should not be the case based on the premises that it is or is not (see Treaty of Human Nature , Book III, Part I).
Since moral distinctions are not based on reason , Hume infers that they are based on feelings that are felt by what he calls “moral sense” .
When we describe an action, feeling or character as virtuous or vicious, it is because your vision causes a particular type of pleasure or pain. Hume is well aware that not all pleasures and pains (for example, the pleasure of drinking good wine) lead to moral judgments. On the contrary, it is “only when a character is considered, in general, without reference to our particular interest, that it causes a sensation or feeling, as it is morally good or bad” ( Treatise on Human Nature , Book III, Part I, sec . 2 ).
Finally, Hume argues that, although moral distinctions are based on feelings, this does not lead to moral relativism. The general moral principles and the faculty of moral sense that recognizes them are common to all human beings.
Space limitations prevent even a superficial sketch of Hume’s treatment of other philosophical issues, such as whether God exists and whether human beings have free will and an immortal soul.
But the devastating impact of Hume’s empiricism on traditional metaphysics is succinctly summed up by closing the lines of his first Investigation . “If we take any volume of divinity or school metaphysics in our hands. . . Let us ask: Does it contain any abstract reasoning about quantity or number? No. Does it contain any experimental reasoning about matter of fact and existence? No. Then commit it to the flames, because it cannot contain more than sophistry and illusion.