To make our idea of morality centre on forbidden acts is to defile the imagination and to introduce into our judgments of our fellow-men a secret element of gusto.

Robert Louis Stevenson (1850-1894) Scottish essayist, novelist, poet

Essay (1888-12), “A Christmas Sermon,” sec. 1, Scribner’s Magazine, Vol. 4
    (Source)

Originally written in the winter of 1887-88. Collected in Across the Plains, ch. 12 (1892).