Occasionalism

The position was developed most influentially by the medieval Islamic theologian al-Ghazali (d. 1111) and later, independently, by the French Cartesian Nicolas Malebranche (d. 1715). The motivation is a combination of theological and philosophical pressure. Theologically, occasionalism maximizes divine sovereignty: every event traces directly back to God's will, with no autonomous creaturely causation intervening. Philosophically, it grows out of a skepticism about whether we actually observe causation — what we observe, as David Hume would later argue, is only regular conjunction of events. Al-Ghazali took this observation and ran with it: if we cannot see causation, maybe there is none at the creaturely level, and what we call causes are just occasions on which God acts.

The classic illustration: when a fire meets cotton, the cotton burns. We call the fire the cause and the burning the effect. The occasionalist says no: the cotton burns because God brings about the burning on the occasion of the fire being present, and God could just as easily not bring about the burning (as in the Qur'anic story of Abraham in the fire, where the fire was present and yet the burning did not occur). The pattern we call natural law is not an intrinsic feature of creation; it is God's regular habit of acting, which he can interrupt whenever he chooses.

Occasionalism has the advantage of making miracles trivially easy — they are just irregular divine acts in a framework where all acts are divine. It also dissolves the mind-body interaction problem, since any apparent interaction between a non-physical mind and a physical body is really just God acting on both in coordination. But it generates its own problems. If God is the sole cause of everything, then human moral responsibility becomes hard to ground (I did not really cause my crime; God did, on the occasion of my willing it). And it makes the world look radically discontinuous at the metaphysical level, even though it looks smooth at the phenomenal level.

Classical Islam absorbed occasionalism deeply through al-Ghazali's influence and it remains a live position in Ash'ari theology. In the Christian tradition it mostly died with Malebranche and was replaced by various kinds of concurrentism (the view that God acts with creatures but does not replace them). For a secular reader, occasionalism is worth knowing because it is the most rigorous version of divine sovereignty on offer and because it previewed Hume's skepticism about causation by six centuries.