One idea is that the counterfactual dependence has to be between separate events. Causation needs to be a natural relation, concerning events that are happening in the world, rather than what Hume called relations of ideas. Some counterfactual dependences will be purely logical, mathematical, or analytic (Hume’s relations of ideas). Others will concern events and facts in the world depending on each other, and that is what interests us.
It needs to be happened
