emotion

In psychology, a powerful feeling; a complex state of body and mind involving, in its bodily aspect, changes in the viscera (main internal organs) and in facial expression and posture, and in its mental aspect, heightened perception, excitement and, sometimes, disturbance of thought and judgement. The urge to action is felt and impulsive behaviour may result.

As a subject area of both biology and psychology, emotion has aroused much controversy. Charles Darwin, in his book The Expression of Emotions in Man and Animals 1872, argued that there are specific, fundamental emotions which are first aroused and then expressed in overt behaviour. William James believed the opposite, namely that emotions actually are the feeling, or sensing, of the bodily changes as they occur when some exciting event or fact is perceived; the Danish physiologist Carl Georg Lange (1834-1900) came independently to much the same conclusion. Their theoretical position, which became known as the James-Lange theory, received considerable criticism at the start of the 20th century. More recently it has been proposed, by US psychologist Stanley Schachter and others, that the visceral changes are more or less the same for all emotions but that the quality of the feelings described - fear, joy, elation, and so on - depend on the individual's cognitive and perceptual evaluation of whatever is new, disruptive, or inconsistent in the environment.