Occasionalism: Causation Among the CartesiansSteven Nadler presents a collection of essays on the problem of causation in seventeenth century philosophy. Occasionalism is the doctrine, held by a number of early modern Cartesian thinkers, that created substances are devoid of any true causal powers, and that God is the only real causal agent in the universe. All natural phenomena have God as their direct and immediate cause, with natural things and their states serving only as occasions for God