An idea · Early Modern · first attested 1739
Causation as Custom
We don't perceive causes. We perceive sequences and form habits.
Hume's most disorienting result. When billiard ball A strikes ball B and B moves, what we perceive is sequence — A, then B — not any "causal" connection between them. Causation, on his analysis, is a habit of expectation produced in us by repeated conjunction. Kant said this was the argument that woke him from his dogmatic slumber.