So far, all that has given color to existence still lacks a history. Where could you find a history of love, of avarice, of envy, of conscience, of pious respect for tradition, or of cruelty? Even a comparative history of law or at least of punishment is so far lacking completely. Has anyone made a study of the different ways of dividing up the day or of the consequences of a regular schedule of work, festivals, and rest. What is known of the moral effects of different foods? Is there any philosophy of nutrition?
—Friedrich Nietzsche, The Gay Science