William of Ockham on Essential Dependence and Causation

It has become a commonly held view that Ockham does not defend a reductionist account of efficient causality, and that for him causal powers cannot be eliminated from causal statements. This paper argues that this reading can be refined, and that according to Ockham the analysis of causality can go one step further. In reaction to Scotus’s concept of essentially ordered causes, Ockham claims that a relation of “essential dependence” holds between a total cause and its effect. I argue for a reading of this relation in counterfactual terms. If this reading is correct, Ockham’s account is close in spirit to the “neo-Humean” account of causality defended by David Lewis, according to which efficient causality is counterfactual dependence plus restrictive clauses concerning cases of counterfactual dependence that are not causal and cases of redundant causation. From this viewpoint, Ockham’s view is close in spirit to the positivist conception of metaphysics that was prevalent before the “neo-Aristotelian” turn in metaphysics.