One hundred and twenty-eight patients who had one or more of the following symptoms or diseases as responses to life situations were studied: urticaria, eczema, cold hands, vasomotor rhinitis, asthma, diarrhea, constipation, nausea and vomiting, duodenal ulcer, migraine, arterial hypertension, and low back pain. Each of these conditions was associated with a particular, completely conscious attitude toward the precipitating situation and thus there were physiological changes specific to each attitude. The changes are biologically appropriate to the attitudes they accompany. It is proposed that emotion be defined to mean an attitude with its associated physiological changes.