[S]leep, and enough of it, is the prime necessity. Enough exercise, and good food and enough, are other necessities. But sleep—good sleep, and enough of it—this is a necessity without which you cannot have the exercise of use, nor the food. – Edward Everett Hale, “How to Get the Best of It,” c.1892

Finish each day before you begin the next, and interpose a solid wall of sleep between the two. – Ralph Waldo Emerson