I’d like to discuss some difficult emotions such as guilt, shame, and embarrassment. These emotions do not have unique facial expressions. Guilt and shame are hard to distinguish from sadness, except for the possibility that the head may be turned away.
The failure to have a distinctive signal for guilt and shame, however, makes sense, since when feeling these emotions the person does not want others to know how he or she feels, and so perhaps a signal did not evolve.Embarrassment is more problematic. The blush doesn’t qualify as an embarrassment signal because it is not observable in everyone. Dacher Keltner has shown that there is not a single momentary expression for embarrassment, as there is for anger, fear, disgust, contempt, sadness, and enjoyment.
Instead, embarrassment is shown through a sequence of expressions overtime. Perhaps embarrassment came late in our evolutionary history and there is not yet been enough time for an efficient signal to have been developed.Envy is another emotion that meets most of the characteristics listed above, with the exception that there does not seem to be a signal. Jealousy I don’t consider an emotion, but an emotional scene or plot, in which there are three actors, the one who fears losing the attention of another, the other and the rival.
Within this plot we can say something about what emotions each person may feel, but that isn’t fixed. The rival could feel guilty, ashamed, afraid, angry, or contemptuous, depending upon the circumstances. The person concerned about losing the interest of the other person might feel angry, afraid, sad, or disgusted.