心理大師馴鴿記

美國著名心理學家 B. F. Skinner 對訓練動物很有一手，曾異想天開地想把鴿子用在軍事用途上。網球教練 Tim Gallwey 在以下段落裡，記載了 Skinner 的一次即場馴鴿示範，並且有所感悟：

Our common tendency to be fooled into chasing rewards which ultimately don't satisfy us reminds me of an experiment conducted by B. F. Skinner, the Harvard behaviorist, on pigeons. I observed this experiment in a course I took in 1957 called Natural Science 114: The Science of Human Behavior. One day Skinner brought out his "Skinner box" with a pigeon inside, and asked the class what we wanted it to do. "Have him jump on his left foot in counterclockwise circles," challenged one of the more arrogant sophomores mockingly.

Within ten minutes, the pigeon was doing exactly that— hopping crazily in counterclockwise circles on his left foot. I was awed and a little frightened. The procedure was so simple. Skinner's cage was equipped with a light, bell and food trough, each of them triggered by a control box which he held in his hand. Skinner simply watched the random behavior of the pigeon until it showed the first element of the desired behavior—say, a weighting of the left foot. At exactly the right moment, he pushed his button, and on went the light, the bell rang, and the food trough opened. The pigeon ate and then continued its random movement until again it leaned on its left foot and again was rewarded with food. Within a few minutes the bird was spending a lot of time on its left foot, but the process had taken quite a while and at this rate it looked as if it would take Skinner hours to train the pigeon to achieve the more complicated requirement of jumping in counterclockwise circles. But now he instituted a trick: with every desired element of behavior the pigeon made, he would push another button which turned on the light and rang the bell, but didn't open the food trough! Thereafter the training proceeded rapidly, since it was no longer interrupted by the pigeon's eating time. The light and bell themselves, by being closely associated with the food, had become sufficient reward to get the bird to do what Skinner wanted, and within five more minutes it was hopping on its left foot in counterclockwise circles.

At that time I had only a faint glimmer of the parallel between the pigeon's fate and my own. At the beginning of the experiment the bird was getting what it really wanted: food. From its point of view, it could be said to be training Skinner to give him food simply by standing on its left foot. Both were getting what they wanted by cooperating. But soon it became clear who was playing whose game. With only a symbolic reward and no real satisfaction, the pigeon was dancing to Skinner's tune, showing itself for what it was: simply a pigeon, conned into working for a false reward.

To be sure, after some time the light and the bell would have lost their power unless reassociated with the real reward, the food. But it seems to be a unique attribute of human beings that they will chase symbolic rewards to the point of death without recognizing that they are missing the real thing. So the smart pigeon discriminates in every situation what winning really means for him, and continually reappraises its goals so that it doesn't exhaust itself chasing appearances.

-- Timothy Gallwey, Inner Tennis (1976, pp. 154-155). Random House.