在一个铁笼子里关着两只猴子,其中一只被捆绑起来,另一只可以在笼里自由活动。每隔一段时间,给铁笼里的猴子一次电击。但是,如果在电击前按下笼子里的一个压杆,就可以免除这次电击。手脚自由的那只猴子知道这种情况之后,为了避免遭到电击,它必须定时去按压杆。这样,它老是记着这件事,提心吊胆,疲于奔命。而手脚被捆绑的猴子反正不能活动,倒省了这份心,落得个清闲自在。数周之后,对两只猴子进行检查,发现能在笼里活动的猴子患有高血压、胃溃疡 Two monkeys are locked in a cage of iron, one of them tied up and the other free to move in a cage. Every once in a while, give the monkey in the cage a shock. However, if you press a pressure lever in the cage before the shock, you are relieved of the shock. After knowing the situation, the monkey, who had free hands and feet, had to press his pole regularly to avoid electric shock. In this way, it always remembered it, scared and exhausted. The hands and feet were bundled monkey can not move anyway, down the heart, set off a leisurely. A few weeks later, two monkeys were examined and found that monkeys that could be caged in the cage had high blood pressure, gastric ulcer