Why You Have No Willpower at Night

It is nine in the evening. You were good all day. Now the packet of biscuits in your hand is empty, and you know the word for it: your willpower ran out. And you know somebody whose willpower never seems to run out. What do they have that you do not have? 0:00 Nine in the evening 0:51 The tank 1:07 The radish room 2:55 59 laboratories 3:39 Where did the worn-out feeling come from? 4:55 Who got further with their goals? 5:56 The question 6:58 Count your own day 7:23 They are asked less often 9:09 Trousers and teeth 10:04 Take away the question 10:56 Nine in the evening, again What the video leaves out, and where it is our own wording: The fuel tank is our picture of the idea. The scientists call the idea "ego depletion". The radish study had a third group that got no food. The video leaves that group out. The two large projects found an effect close to zero. One of them found a small effect among people who said that they felt tired. The video says so. The study at McGill University is one study of students, over one week, from their own answers. About two in three students answered at the end of the term. The result is a link between people, and the authors say that it needs to be repeated. The video says so. "Do I, or don't I?" is our wording of the authors' guess. We did not read the full text of the beeper study. Two later papers report its result, and the video gives it in one sentence. The study of 500 adults is one of six studies in its paper, and its links are modest. The video says so. The trousers, the teeth, the shop shelf and "shoes on at seven" are our examples. They are not from a study. Each figure is a simple drawing. The student in the radish room and the student in the library stand for groups of people. This video is not medical or psychological advice. Sources: Baumeister, Bratslavsky, Muraven and Tice, 1998, Journal of Personality and Social Psychology (the radish study) Hagger and others, 2016, Perspectives on Psychological Science (23 laboratories) Vohs and others, 2021, Psychological Science (36 laboratories) Milyavskaya and Inzlicht, 2017, "What's So Great About Self-Control?", Social Psychological and Personality Science 8(6) Hofmann, Baumeister, Förster and Vohs, 2012, "Everyday temptations", Journal of Personality and Social Psychology 102(6) Galla and Duckworth, 2015, Journal of Personality and Social Psychology 109(3) Adriaanse, Kroese, Gillebaart and De Ridder, 2014, Frontiers in Psychology 5:444