The brother of Harriet Martineau was born in Norwich in 1805. He was ordained in the Unitarian ministry in 1828, and served as a minister in Dublin and Liverpool. In 1841 he was appointed professor of moral philosophy at Manchester New College. While at Manchester he published his first influential book, Endeavours After the Christian Life (1843). In 1869 he became principal of the college and wrote several books on religion and philosophy including A Study of Spinoza (1882), Types of Ethical Theory (1885), A Study of Religion (1888) and the Seat of Authority in Religion (1890).