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According to psychologists, there’s a limit to how much willpower mortals can exercise at once. College students were the subject of this study.

Cookie or Radish: Which One do You Prefer?

If you were one of the students in this study, you had no say in the matter. A group of students were told they were participating in a study about “food perception”  and were asked not to eat for three hours before arriving. Upon their arrival, all of them were taken to a room that smelled great because the researchers baked chocolate-chip cookies a few minutes beforehand.  A table in the middle of this room had two bowls. The first had fresh baked cookies and the other contained radishes.

The Cover Story

The clever researchers told the students they selected chocolates and radishes because of each food’s highly distinctive taste. In addition, they would contact the students the following day to evaluate their memory of the taste distinctions the students experienced.

  • Cookie-eating group: Half the participants could eat two cookies, but no radishes.
  • Radish-eating group: The other half could eat at least two radishes, but no cookies.

    While the students ate, the researchers left the room in hopes of inducing temptation in the students – especially the radish group. Still, everyone stayed on course. The “taste study” was complete…or that’s what the students were told.
A Puzzling Job

Here comes the typical con artistry necessary for many psychological studies. A different group of lab coats entered with a completely unrelated study for the students, which was secretly part of the original study. These new researchers told the college students they were testing who was better at solving puzzles – college or high school students.

The college students agreed to participate and were then given some puzzles that involved tracing complex shapes – but remained unaware of one caveat. The puzzles were unsolvable – the researchers wanted to test the students’ persistence.

The Con Conclusion

The cookie-eating group spent 19 minutes on the task, while the radish-eaters gave up after 8 minutes. Why? The researchers concluded that the radish-eaters “ran out” of self-control, and that self-control is an exhaustible resource.

That’s why the radish group gave up 11 minutes faster – they spent all of their will power on resisting the cookies during the previous study. This makes sense, considering another recent study concluded that on a biological level, there’s an inverse relationship between resisting temptation and brain glucose levels. The brain demands glucose while performing tasks, so the depleted group’s (depleted from resisting cookies) lack of will can be attributed to biological factors. Fair enough. If you’re resisting too many things at once, you might give up quicker than if you executed things one at a time like a Zen monk.

 “Yard by yard, life is hard. But inch by inch, life’s a cinch.”


6 Responses to The Limits of Willpower

  1. newman says:

    thank you excellent read.

  2. power factor says:

    Very helpful post man, thanks for the info.

  3. goddess588 says:

    That’s why you should never go on a diet and try to quit smoking at the same time.

  4. Aaron Michael says:

    What was the study? Who were the authors?

  5. [...] and willpower should be thought of as muscles.  Muscles get stronger the more you use them BUT they can also be strained from overuse.  If it’s a constant mental struggle to achieve your goals, you will get tired and [...]

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