Education can counteract the natural tendency to do the wrong thing, but the inexorable succession of generations requires that the basis for this knowledge be constantly refreshed.

Value is a relative concept: the value of each action is determined by comparing it with other possible actions.

Incommensurables cannot be compared.

The rational man finds that his share of the cost of the wastes he discharges into the commons is less than the cost of purifying his wastes before releasing them.

But as population became denser, the natural chemical and biological recycling processes became overloaded, calling for a redefinition of property rights.

Ruin is the destination toward which all men rush, each pursuing his own best interest in a society that believes in the freedom of the commons.

There is nothing more dangerous than a shallow thinking compassionate person