Comment: A general "theory of emotion" is neither necessary nor possible

Progress in emotions research requires understanding why debate about the general nature of emotions remains intractable. Much confusion arises from proposals that offer one of the four different kinds of biological explanation, without recognizing the need for other three. More arises from tacitly thinking of emotions as products of design, when they are actually organically complex products of natural selection. Finally, debate persists because of categorizing emotions by functions, instead of recognizing that each emotion was shaped by the adaptive challenges posed by a recurring situation. No general explanation of the kind usually sought for emotions exists, however progress is possible if we study emotions as organically complex partially differentiated constellations of changes that have been useful in certain situations.