Once when I asked him why he had never ventured on a Treatise he answered, with his characteristic smile and chuckle, that large-sclae enterprise, such as Treatises and marriage, had never appealed to him. It may be that the deemed them industries subject to diminishing return, or that they lay outside his powers or the limits he set to his local universe.

John Maynard Keynes, ‘Francis Ysidro Edgeworth’, in Essays in Biography, London, 1933, p. 232