 On the other hand, it also resurrects with renewed vigor some of the problems considered above. Most notably, if ideas are abstract, logical entities, then they are even more difficult to reconcile with Malebranche’s substance-mode ontology. Indeed, one commentator has argued that, to avoid inconsistency, Malebranche ought to have made a clean break with the Cartesian assumption that everything is either a substance or a mode in favor of a more ‘trialistic’ view that grants that ideas, qua third realm entities, are sui generis (Jolley 1990, 79). As abstract entities, it is also difficult to understand how ideas can have causal powers, in keeping with the doctrine of efficacious ideas, or how they can be identical with God’s substance (Jolley 1990, 76f). In Malebranche’s defense, one might note that the latter problem arises only from regarding ideas as logical entities. Perhaps ideas in God should not be conceived in this manner (Pepper-Bates 2005, 93).