Causation, in modern philosophy

The new science of the sixteenth and seventeenth centuries sparked intense reflection and theorizing on the nature of causation. Philosophers attempted to account for the nature of causation in a way that would satisfy the demands of metaphysics, theology and science. Against the Aristotelian tradition, Descartes defends a view of the nature of matter as essentially inactive, thus obviating the metaphysical problem of the nature of change. Interactionism emerges as a scientifically attractive position, but it seems to violate some fundamental tenets of Cartesian metaphysics. Occasionalism, the metaphysical doctrine according to which God is the only cause of change, seems appealing on religious/theological grounds but raises difficult questions about our relation to the natural world and thus about the nature of science. Occasionalism, however, seems inevitable once Malebranche powerfully argues that necessary connection is the most essential element of the concept of causation. The element of necessary connection makes it logically impossible for the effect to fail to follow from the cause. Only God’s will satisfies the requirement that the effect cannot fail to follow from the cause without contradiction. Thus God is the only true cause of everything. While mounting powerful criticisms of both occasionalism and interactionism, Hume manages to include necessary connection in at least one of his definitions of cause. For Hume, our idea of necessary connection originates in an impression of reflection or a determination of thought prompted by our experience of constant conjunctions. Our causal inferences are the products of habit and the imagination, rather than reason. Unlike most modern philosophers, Leibniz defends a view of created substances as essentially active and ascribes a central role to final causation. Leibniz’s doctrine of pre-established harmony endows each created substance with the capacity of change, but denies the possibility of genuine interaction between substances. Kant rejects Leibnizian pre-established harmony, which he conceives as rendering causation merely ideal, and argues in favour of a Newtonian interactionist model: a spatio-temporal world of material substances that causally interact with one another. Against Hume, Kant defends the concept of cause as a pure concept of the understanding that can be rightfully applied to the objects of experience. Indeed, Kant argues that without the concept of cause we could not have any experiences whatsoever. Women philosophers were also part of the philosophical debates concerning causation in the modern period, mounting powerful arguments against the most established positions. Cavendish attacks interactionism, arguing that motion cannot transfer from one body to another. Astell criticizes occasionalism on the grounds that it renders God a poor craftsman who acts in vain by creating bodies which do not play any role whatsoever. Shepherd levels some strong objections against Hume’s imagination-based account of causation and she insists on the role of reason in achieving knowledge of causation.