Full Idea
Causation relations between events may an instance of a causal law, with laws either interpreted as constant conjunctions (Hume), or as necessitation among universals (Armstrong).
Gist of Idea
Causation may be instances of laws (seen either as constant conjunctions, or as necessities)
Source
E.J. Lowe (A Survey of Metaphysics [2002], p.190)
Book Reference
Lowe,E.J.: 'A Survey of Metaphysics' [OUP 2002], p.190
A Reaction
Hume's version is a thin idea of a law, but we can dream about the metaphysical status of laws, even if we don't know much about them. Lowe says a cause without a law is perfectly intelligible.