What is occasionalism’s explanation for the apparent interaction between mind and body?

In Cartesian philosophy, occasionalism posits that the mind and body do not interact directly because they are fundamentally different substances—one being unextended and thinking, the other being extended and passive.1

Instead, occasionalists argue that the apparent interaction between these two realms is mediated entirely by God. In this view, mental and physical events are coordinated by divine intervention rather than direct causation. For example, when a person wills to move their arm, that act of will serves merely as an "occasion" for God to intervene and move the body. Similarly, when a person encounters a physical object, that contact acts as an occasion for God to produce corresponding ideas within the person's mind.12

Developed by philosophers such as Arnold Geulincx and Nicolas Malebranche, this theory was intended to resolve the difficulty of explaining how an immaterial mind could influence a material body, a problem that remained unresolved in René Descartes's own account of the pineal gland.13