Social Dilemmas

Abstract Consider a simple situation. A number of people sit around a large bowl, which contains a dozen walnuts. Once taken, the walnuts may be traded for something valuable — money or food, for example. The people are told that they may take as many walnuts out of the bowl as they wish at any time; turn‐taking is not required. They are ready to grab as many walnuts from the bowl as they can when they are given one more piece of information: If any walnuts remain in the bowl ten seconds after the start, I will place that many more walnuts in the bowl. How many walnuts should they take? How many will be taken?