Thomas Edison, Power-Napper: The Great Inventor on Sleep & Success: "People will not only do what they like to do — they overdo it 100 per cent. Most people overeat 100 per cent, and oversleep 100 per cent, because they like it. That extra 100 per cent makes them unhealthy and inefficient. The person who sleeps eight or ten hours a night is never fully asleep and never fully awake — they have only different degrees of doze through the twenty-four hours. … For myself I never found need of more than four or five hours’ sleep in the twenty-four. I never dream. It’s real sleep. When by chance I have taken more I wake dull and indolent. We are always hearing people talk about ‘loss of sleep’ as a calamity. They better call it loss of time, vitality and opportunities. Just to satisfy my curiosity I have gone through files of the British Medical Journal and could not find a single case reported of anybody being hurt by loss of sleep. Insomnia is different entirely — but some people think they have insomnia if they can sleep only ten hours every night."
