There is a philosopher said that if you sleep two hours a day, you live more than ten years. Legend of the great people or hard-working people are less rest groups. Energetic people sleep less. There are two explanations. One is that they do not need so much sleep, because the brain secrete more nerve hormones, enough to keep people conscious and emotional . So they are creative. Scientists, writers, artists, politicians are often sleepless all the night, and they are not entirely influenced by circadian rhythms. If you accept this explanation, then the people sleep more maybe lazy than those who sleep less . Lack of creativity, but also less passion for life. The second explanation is that human have great individual specificity. [...]