  The first philosophical influence on Wright was the Scottish realist, Sir William Hamilton, whose works formed the curriculum for Francis Bowen's teaching of philosophy at Harvard. Wright was, however, greatly influenced by John Stuart Mill's criticism of Hamilton, and the influence of Mill is evident in Wright's views on utility in science and ethics. The great conversion of his life came, however, with his reading of Darwin's Origin of Species, published in 1859. Wright became an American defender of Darwin against his religious antagonists and also, like Harvard's Asa Gray, against Darwin's scientific critics in America.