1617 – 1688
Ralph Cudworth (1617–1688) was an English philosopher and theologian, the foremost systematic thinker among the Cambridge Platonists. He opposed Hobbesian materialism, Calvinist determinism, and moral voluntarism, arguing that reason and eternal moral truths are grounded in the divine intellect rather than arbitrary divine will. His major work, The True Intellectual System of the Universe, remains one of the most ambitious defenses of theistic rationalism in early modern philosophy.
Authored The True Intellectual System of the Universe (1678), a comprehensive refutation of materialist atheism
Developed the doctrine of 'plastic nature' as a subordinate, non-mechanical principle mediating divine action in the world
Defended eternal and immutable moral truths against voluntarist ethics in A Treatise Concerning Eternal and Immutable Morality (posthumous, 1731)
Argued against Calvinist necessitarianism in defense of human free will and moral responsibility
Synthesized Neoplatonic metaphysics with Christian theology as a counter to Hobbes and Descartes