Thomas Alva Edison (February 11, 1847 – October 18, 1931) was an American inventor and businessman who has been described as America’s greatest inventor. Edison used napping to counterbalance the intensity of his work. Most days, he took one or two brief naps — on his famous cots, outdoors in
Leonardo da Vinci (14/15 April 1452 – 2 May 1519) was an Italian polymath of the High Renaissance who is widely considered one of the most diversely talented individuals ever to have lived. Leonardo da Vinci slept for only 20 minutes every four hours. There was no long nighttime sleep for him.