Science and Health with Key to the Scriptures

Science and Health with Key to the Scriptures is the textbook of Christian Science, presenting an absolutist metaphysics in which matter, disease, and evil are unreal and only Spirit, or God, truly exists. Healing follows as the mental recognition of this truth and the correction of a false belief in matter.

The work develops a systematic, scripture-based doctrine, pairing a metaphysical argument with a re-reading of the Bible, and transforms the practical mind-healing Eddy had earlier encountered into a closed theological system with its own trained practitioners. She presented it as divine revelation rather than borrowed method, a claim that drew lasting controversy.

Its significance is to push mental causation to its limit and to institutionalise it. Bequeathing to New Thought the influential and contested distinction between a real spiritual realm and an illusory material one, it underpinned the most organised and enduring of the nineteenth-century mind-healing movements.