" His reaction looked very much like anger, with threatening gestures, raised voice, and a purple face. But his anger was triggered by apprehension and was mixed with hope that some good discipline might keep me from being so stupid again. It sure did! My point here is that every display of emotion needs to be judged in a wider context. A single label rarely suffices. To call my father's state "angry" fails to do it justice without also mentioning love and worry. "

― Frans de Waal , Mama's Last Hug: Animal Emotions and What They Tell Us about Ourselves