There is an inconvenience which attends all abstruse reasoning. That it may silence, without convincing an antagonist, and requires the same intense … - David Hume

But where the ideas of morality and decency alter from one age to another, and where vicious manners are described, without being marked with the proper character of blame and disapprobation, this must be allowed to disfigure the poem, and to be a real deformity. I cannot, nor is it proper I should, enter into such sentiments; and however I may excuse the poet, on account of the manners of age, I can never relish the composition.

Morals excite passions, and produce or prevent actions. Reason of itself is utterly impotent in this particular. The rules of morality, therefore, are not conclusions of our reason.

Long before we have reached the last steps of the argument leading to our theory, we are already in Fairyland