Before discussing different kinds of emotions,let us briefly talk about how researchers measure bodily processes and action or behavior,and how this relates to what we do in our daily lives when we observe emotions in others.

    Bodily processes can be directly measured by means of a polygraph.When a polygraph is skillfully used to compare how we react bodily with what we are saying,it is called a “lie detector”.Bodily processes can also be measured indirectly.This is what we do when we observe someone blushing (脸红).However,we are not always aware of what bodily processes respond to.

    Measuring action or behavior is the other way researchers assess the emotions.For example,one measure of fear of snakes is how close a person will go to the snake.Another procedure is to have a person tell how afraid he is,or how he feels.In this way,researchers have developed the so－called “fear thermometer” to assess a person's fear.In our everyday living,we do very much the same thing.Only not too systematically,we react to what a person does, what he says,how he says it,and how he looks.Is he smiling? Is his voice trembling? We put all this observations together to infer what a person is feeling.

    However, we do not always act as we feel.Sometimes we do things that we don't feel like doing.Sometimes we say we feel one way and then we act another.Actors,for example,successfully learn to “make believe” emotions,or learn to hide them.Thus we cannot always tell what a person is feeling by what he says or by what he does.

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