The Cambridge History of English and American Literature in 18 Volumes (1907–21). Volume XIV. The Victorian Age, Part Two. I. Philosophers. § 12. Jevons. For more than a generation Mill’s influence was dominant in all departments of philosophical and political thought; he had the initiative, and set the problems for his opponents as well as for his adherents; and his works became university text-books. This holds of politics, economics, ethics, psychology and logic. A striking reaction against his influence is shown in the work of William Stanley Jevons, professor at Manchester and afterwards in London, whose economic and logical writings are distinguished by important original ideas. In his Theory of Political Economy (1871), he introduced the conception of final (or marginal) utility, which, subsequently, has been greatly developed in the analytic and mathematical treatment of the subject. In logic, also, he laid the foundations for a mathematical treatment in his Pure Logic (1864) and Substitution of Similars (1869); and, in his Principles of Science (1874), he fully elaborated his theory of scientific inference, a theory which diverged widely from the theory of induction expounded by Mill. As time went on, Jevons became more and more critical of the foundations of Mill’s empirical philosophy, which he attacked unsparingly in discussions contributed to Mind.   37