Chauncey Wright, the American philosopher and mathematician, was born in Northampton, Massachusetts. On the surface, his life was completely uneventful. From 1852 to 1870 he worked as a mathematician for the Nautical Almanac; he was twice a lecturer at Harvard College—in psychology in 1870 and in mathematical physics in 1874—and he occasionally tutored private pupils. In 1860 he was elected a fellow of the American Academy of Arts and Sciences, of which he was later secretary. He visited Charles Darwin in England in 1872—the major social event of his life. Between 1864 and 1875 he contributed numerous articles to the North American Review and the Nation. His longer articles were published posthumously in 1877 under the title Philosophical Discussions; his Letters appeared in 1878.

Wright was not successful as a lecturer, but he was a splendid tutor, and many interested individuals sought to converse with him. It was through this easy...