So the trick in designing these kinds of situations is to understand where you're relying on the economic part of the bargain -- as with the parents paying the teachers -- and when you're relying on the social part of the bargain, when you're really designing for generosity.
Tako je trik u stvaranju ovih vrsta situacija razumjeti gdje se oslanjate na ekonomski dio pogodbe - kao što su roditelji plaćali odgajateljima - a kad se oslanjate na društveni dio pogodbe, kada zaista stvarate iz velikodušnosti.