Emotion is a feeling about or reaction to certain important events or thoughts. People enjoy feeling such pleasant emotions as love, happiness, and contentment. (41)________

Individuals communicate most of their emotions by means of words, a variety of sounds, facial expressions, and gestures. (42)________People learn ways of showing some of their emotions from members of their society, though heredity may determine some emotional behaviour. (43)________

Charles Darwin, famous for the theory of natural selection, also studied emotion. Darwin said in 1872 that emotional behaviour originally served both as an aid to survival and as a method of communicating intentions. According to the James-Lange theory of emotions developed in the 1880s, people feel emotions only if they are aware of their own internal physical reactions to events, such as increased heart rate or blood pressure. (44)________The cats could not feel their body‘s internal changes, but they showed normal emotional behaviour. John B. Watson, an American psychologist who helped found the school of psychology called behaviourism, observed that babies stimulated by certain events showed three basic emotions—fear, anger, and love. Watson‘s view has been challenged frequently since he proposed it in 1919.

The most widely accepted view is that emotions occur as a complex sequence of events. The sequence begins when a person encounters an important event or thought. The person‘s interpretation of the encounter determines the feeling that is likely to follow. (45)________

The sense of danger would cause the individual to feel fear. Each feeling is followed by physical changes and desires to take action, which are responses to the event that started the sequence. Thus, a person who met a bear would probably run away.

A. For example, someone who encounters a bear in the woods would probably interpret the event as dangerous.
B. But this theory was not upheld by research on cats that had their nervous systems damaged.
C. Several American psychologists independently developed the theory that there are eight basic emotions.
D. They often try to avoid feeling unpleasant emotions, such as loneliness, worry, and grief.
E. For example, anger causes many people to frown, make a fist, and yell.
F. They combine to form all other emotions, just as certain basic colours produce all others.
G. Research has shown that different isolated peoples show emotions by means of similar facial expressions.