Although David Hume (1711-1776) is widely considered a skeptic about matters of metaphysics, he is not a skeptic about morality.
Hume's philosophy is a response both to a materialistic view of the world (that everything is just matter and motion) and to moral rationalism.
If good and evil are not "out there" then they must be "in there," inside human beings, perhaps in the mind.
Hume believes that good and evil exists and locates the source of morality within human beings.
According to Hume, there are only two kinds of reason: mathematical or logical reasoning ("realtions of ideas") and empirical reasoning about the properties of material objects ("matters of fact") (Enquiry, p. 84).
The most important sentiment Hume believes to be universal is the sentiment of benevolence. Contra Hobbes, Hume believes we are all attracted by actions that benefit others.
"The epithets sociable, good-natured, humane, merciful, grateful, friendly, generous, beneficient, or their equivalents, are known in all languages, and universally express the highest merit, which human nature is capable of attaining." (Enquiry, 16-17).