At the Harvard Symposium for Hard Problems in Social Science , Emily Osterpresented a very simple, elementary problem: almost all people with type-2diabetes who are overweight can be cured by losing a little bit of weight. They aremade aware of it, yet they usually gain weight a�er diagnosis (she mentioned”Atkins” among the options, so it was not just AMA low-fat.). It is so obvious thatwe know what to do yet do not carry the action because thinking can be largelyornamental. The proof of the sterility of (a significant class of) knowledgesterility of (a significant class of) knowledge was rightthere (among the obvious evidence that the population has been gaining weight inspire of technological and educational progress). Yet the others social scientistskept exalting the value of “education” in spite of this simple devastating evidence.Someone even suggested teaching more “critical thinking”. This is the great suckerproblem: people who teach truly think that teaching, or, worse, preaching, cures.