There are resources which belong to us all, for example, fresh water, clean air and healthy oceans. Unfortunately, human nature has a tendency to exploit these vital resources for selfish and short-term rewards. Although it would be nice and simple, it does no good to exhort individuals to be less selfish. So, what happens? Benefits accrue to the exploiter and the costs are borne by all of us. The resource is eventually depleted or ruined and lost to everyone. There . . .