 Leibniz’s account of mind-body causation was in terms of his famous doctrine of the pre-established harmony. According to the latter, (1) no state of a created substance has as a real cause some state of another created substance (i.e. a denial of inter-substantial causality); (2) every non-initial, non-miraculous, state of a created substance has as a real cause some previous state of that very substance (i.e. an affirmation of intra-substantial causality); and (3) each created substance is programmed at creation such that all its natural states and actions are carried out in conformity with all the natural states and actions of every other created substance.