James Martineau (born April 21, 1805, Norwich, Norfolk, England—died January 11, 1900, London) was an English Unitarian theologian and philosopher whose writings emphasized the individual human conscience as the primary guide for determining correct behaviour. He was a brother of writer Harriet Martineau.
From 1828 to 1832 Martineau served as junior minister at Eustace Street (Unitarian) Church, Dublin, leaving on the death of his senior for a position in Liverpool. There he began to question the traditionally authoritative role of Scripture, and in his Rationale of Religious Inquiry (1836) he declared that “the last appeal in all researches into religious truth must be to the judgment of the human mind.” Appointed professor of mental and moral philosophy at Manchester New College in 1840, Martineau taught there (and from 1869 served as principal) until 1885, searching for an alternative to biblical authority, especially in such later works as Types of Ethical Theory (1885), A Study of Religion (1888), and The Seat of Authority in Religion (1890).