White is a colour. It is not the absence of colour; it is a shining and affirmative thing, as fierce as red, as definite as black. When, so to speak, your pencil grows red-hot, it draws roses; when it grows white-hot, it draws stars. And one of the two or three defiant verities of the best religious morality, of real Christianity, for example, is exactly this same thing; the chief assertion of religious morality is that white is a colour. Virtue is not the absence of vices or the avoidance of moral dangers; virtue is a vivid and separate thing, like pain or a particular smell. Mercy does not mean not being cruel or sparing people revenge or punishment; it means a plain and positive thing like the sun, which one has either seen or not seen.
GKC – A Piece of Chalk