He was born in Farmington, Conn., in 1811. In 1831, he graduated from Yale and two years later became a tutor in the college. During these years he studied theology and in 1836, he became pastor of the Congregational Church at Milford. During the ten years following he had charge of several Congregational churches. In 1846 he returned to New Haven to take the chair of Clark professor of metaphysics and moral philosophy in the college. It was in 1853 that Yale sent him to Germany to study modern German philosophy. Five years later he received the degree of D. D. from the University of New York.
In 1871 he was elected president of Yale College to succeed Dr. Theodore Dwight Woolsey and in the same year Trinity conferred on him the degree of LL. D. He resigned the presidency in 1886, the year that the college was made a university.
In 1864 and again in 1880, Dr. Porter supervised the revision of Webster's Dictionary. He was the author of the celebrated book on "The Human Intellect," published in 1868 which has become an accepted text-book in many American colleges. He also wrote a large number of metaphysical works.