What was Williams James’ main contribution to psychology?
James developed the same theory that was independently developed by Carl Georg Lange (1834–1900), the Danish physician and psychologist. It became known as the James–Lange theory of the emotions. The theory is that emotions are our experience of changes in our bodies. Benedict de Spinoza (1632–1677) had held that emotions are the effects of our beliefs, while René Descartes (1596–1650), in Passions of the Soul (1649), had expressed an earlier version of the James-Lange theory.
Our common sense assumption is that emotions are reactions to events in the world that are mediated by our understanding. By contrast, the James–Lange theory held that our bodies react directly to the world and our awareness of this physical reaction constitutes our emotions. In “What Is an Emotion?,” his famous 1884 article published in Mind, James wrote:
Our natural way of thinking about … emotions is that the mental perception of some fact excites the mental affection called emotion, and that this latter state of mind gives rise to the bodily expression. My thesis on the contrary is that the bodily changes follow directly the perception of the exciting fact, and that our feeling of the same changes as they occur is the emotion.