It occurs to me that the malfunctions of the fast mind may help explain why it is so hard to lose weight. Consider the well known principle of caloric leakage, the principle that holds that although a cookie has lots of calories, a piece of a broken cookie does not, the calories having leaked out—so you might as well eat it. Or consider my well established weakness for marginal cost zero food—another serving at an all-you-can-eat buffet.Lew says toss the cookie crumble equations, go primal, and just eat like you are supposed to.
The explanation for caloric leakage is the inability of my fast mind to deal with fine distinctions—a piece of a cookie is entirely different from a cookie, cannot be viewed as half a cookie, and so my knowledge that it has half the calories of the cookie never gets triggered. The explanation for the second problem is that, faced with zero marginal cost food, I have no need to pass the decision of whether to eat it on to my slow mind to decide whether it is worth the cost in money—and my fast mind doesn't worry about the cost in calories.