I shall argue in this paper that extant definitions of causality are incorrect since they do not cohere in the proper way with the concept of a cause of the universe. This lack of coherence is twofold. For some extant definitions of a cause, there are possible instances of the concept of a cause of the universe that do not satisfy the definitions. For these or other extant definitions, there are entities or occurrences that are not instances of the concept (...) of a cause of the universe but that count as causes of the universe according to the definitions. This failure of coherence between extant definitions of causality and the concept of a cause of the universe entails either that there is some other definition of a cause that is correct or that causality is indefinable. I shall suggest in the conclusion of this paper that it is more plausible to believe that causality is indefinable. (shrink)