 To see how Reid is thinking about the strength of motives, consider a case in which you are moved to action by some animal principle of action. Imagine, for example, you are incited to reprimand someone in your family because you believe that he or she has acted irresponsibly by leaving a kitchen light on during the night. One way to assess this action would be to ask whether it conforms to the rational principles of action. Let us suppose that, in the case we are considering, by reprimanding you risk alienating yourself from those with whom you live; the circumstances you’re in call for a calm and measured response. While there may be good reasons to alienate yourself from others, expressing your anger in these circumstances is not one of them. This motive in these circumstances, then, has no rational authority.