I recall once saying that when I had given the same lecture several times I couldn't help feeling that they really ought to know it by now.
John Edensor LittlewoodI read in the proof sheets of Hardy on Ramanujan: "As someone said, each of the positive integers was one of his personal friends." My reaction was, "I wonder who said that; I wish I had." In the next proof-sheets I read (what now stands), "It was Littlewood who said..."
John Edensor LittlewoodA precisian professor had the habit of saying: "... quartic polynomial ax^4+bx^3+cx^2+dx+e , where e need not be the base of the natural logarithms."
John Edensor LittlewoodA good mathematical joke is better, and better mathematics, than a dozen mediocre papers.
John Edensor Littlewood