No, Sir, it is a good thing; there is a community of mind in it. Classical quotation is the parole of literary men all over the world. – Samuel Johnson, quoted in The Life of Samuel Johnson by James Boswell, Volume II

What a good thing Adam had — when he said a good thing, he knew nobody had said it before. – Mark Twain, 1867

Precepts or maxims are of great weight; and a few useful ones at hand do more toward a happy life than whole volumes that we know not where to find. – Seneca

There is hardly a mistake which in the course of our lives we have committed, but some proverb, had we known and attended to its lesson, might have saved us from it. – Richard Chenevix Trench, Proverbs and Their Lessons, 1905