when it is active, shows no fatigue at all! If we took a drop of blood from a day laborer, we would find it full of fatigue toxins at and fatigue products.But if we took blood from the brain of an Albert Einstein, it would show no fatigue toxins at the end of the day.

　　So far as the brain is concerned， it can work as well and swiftly at the end of eight or even twelve hours of effort as at the beginning.The brain is totally tireless.So what makes us tired?

　　Some scientists declare that most of our fatigue comes from our mental and emotional attitudes. One of EnglanD s most outstanding scientists, J．A.Hadfield, says, “The greater part of the fatigue from which we suffer is of mental origin.In fact, fatigue of purely physical

　　origin is rare.” Dr Brill, a famous American scientist, goes even further. He declares, “One hundred percent of the fatigue of sitting worker in good health is due to emotional

　　problems.”

　　What kinds of emotions make sitting workers tired? Joy? Satisfaction？ No! A feeling of being bored, anger, anxiety, tenseness, worry, a feeling of not being appreciated—those are the emotions that tire sitting workers. Hard work by itself seldom causes fatigue. We get tired because our emotions produce nervousness in the body.

　　本文介绍的是一项新的研究成果：单独的脑力劳动不会使我们感到疲倦，真正让我们感到累的原因是我们的情绪。

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