  Commentators have proposed various interpretations to avoid these difficulties.  One approach is to construe ‘reason’ as the name of a process or activity, the comparing of ideas (reasoning), and to construe ‘morals’ as Hume uses it in this argument to mean the activity of moral discrimination (making a moral distinction).  If we understand the terms this way, the argument can be read not as showing that the faculty of reason (or the beliefs it generates) cannot cause us to make moral judgments, but rather as showing that the reasoning process (comparing ideas) is distinct from the process of moral discrimination.  This interpretation does not rely on an assumption about the transitivity of causation and is consistent with Hume’s theory of causation.