British philosopher and Anglican theologian and priest remembered for his exposition of the philosophy of the Scottish thinker Sir William Hamilton (Hamilton, Sir William, 9th Baronet) (1788–1856).

Educated at the University of Oxford, Mansel was elected Waynflete professor of moral and metaphysical philosophy there in 1859. In 1866 he was appointed regius professor of ecclesiastical history and canon of Christ Church. Two years later he became dean of St. Paul's.

Most of Mansel's philosophical works centre on the relation between human thought and human experience. For the eighth edition of the Encyclopædia Britannica (1857) he wrote an article on metaphysics in which he discussed this relationship and developed Hamilton's views. In his Bampton Lectures, The Limits of Religious Thought (1858), Mansel expounded Hamilton's doctrine that human knowledge is strictly limited to the finite and is “conditioned.” In reply to attacks on this notion by John Stuart Mill and other critics, Mansel defended Hamilton's views in The Philosophy of the Conditioned (1866). His contention, however, that the human mind could not attain to any positive conception of the nature of God or his goodness provoked considerable controversy, and Mansel, who meant to attack deism, rather than theism, was accused of agnosticism. Concerned with problems of language and logic, Mansel discussed the verification of the meaning of different propositions and stressed the fundamental difficulty of arriving at particular truths. General knowledge, as his “Metaphysics” article indicated, is humanly possible, but specific truths are inscrutable. Consequently, faith is required in order to overcome the dilemma between the existence of evil and the goodness of God. Among Mansel's other writings are Prolegomena logica: An Inquiry into the Psychological Character of Logical Processes (1851) and The Gnostic Heresies of the First and Second Centuries (1875); with J. Veitch he edited Hamilton's Lectures on Metaphysics and Logic, 4 vol. (1859–60).