[From Greek automatismos: that which happens on its own.]
(metaphysics) The doctrine that the actions of animals are mechanistically determined. In particular, this doctrine is one constituent of Cartesianism, since Descartes (1596-1650) advocated a strict determinism or mechanism in biology. Although automatism has little basis in biological fact, its core beliefs have persisted into recent times under different names (e.g., see behaviorism).