Book excerpt: Originally published in 1987. The Origins of Agnosticism provides a reinterpretation of agnosticism and its relationship to science. Professor Lightman examines the epistemological basis of agnostics' learned ignorance, studying their core claim that "God is unknowable." To address this question, he reconstructs the theory of knowledge posited by Thomas Henry Huxley and his network of agnostics. In doing so, Lightman argues that agnosticism was constructed on an epistemological foundation laid by Christian thought. In addition to undermining the continuity in the intellectual history of religious thought, Lightman exposes the religious origins of agnosticism.