Conway Hall Ethical Society has an interesting history, which shows the Christian origins of Progressive Secular Humanist memeplex.

The Conway Hall Ethical Society, formerly the South Place Ethical Society, based in London at Conway Hall, is thought to be the oldest surviving freethought organisation in the world, and is the only remaining ethical society in the United Kingdom. It now advocates secular humanism and is a member of the International Humanist and Ethical Union.

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The Society was formed in 1793 by a group of nonconformists known as Philadelphians or Universalists. William Johnson Fox, who had studied theology under Dr Pye Smith, became minister in 1817. In 1824 the congregation built a chapel at South Place, in the district of central London known as Finsbury

Conway Hall is named after an American, Moncure Conway, who led the Society from 1864–1885 and 1892–1897, during which time it moved further away from Unitarianism. Conway spent the break in his tenure in the United States, writing a biography of Thomas Paine. In 1888 the name of the Society was changed from South Place Religious Society to South Place Ethical Society (SPES) under Stanton Coit's leadership.