 Davidson argues for the cause-law principle—that singular causal relations require strict covering laws—on the basis of a conceptual interconnection between the concepts of physical object, event and law. As he says, “our concept of a physical object is the concept of an object whose changes are governed by laws” (Davidson 1995a, 274). The interconnections are established partly in response to C.J. Ducasse’s attempt, in reaction to Hume’s regularity theory of causation, to define singular causal relations without appeal to covering laws (Ducasse 1926).