According to the Yale Book of Quotations, the Disraeli theory is supported by a July 27, 1895 attribution in the London Times, strengthening the claim by Twain. Robert Giffen uses a similar quote in a June, 1892 Economic Journal article. And there are other citations that attribute it or something similar to "the Wise Statesman" or "a witty statesman" that the Yale entry says could strengthen the Disraeli theory. I just saw something else called The Quote Verifier that puts some doubt back in the Disraeli theory. It adds a bunch more usages and other possibilities of who said it first, including "a recent President of Harvard" (1896) and Tennyson. Mathew Forstater