William Makepeace Thackeray, Vanity Fair or, A Novel without a Hero (London: Thomas Nelson and Sons, n.d.; 1847-1848), p. 12:
The world is a looking-glass, and gives back to every man the reflection of his own face. Frown at it, and it will in turn look sourly upon you; laugh at it and with it, and it is a jolly kind companion; and so let all young persons take their choice.