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. Freedom in a commons brings ruin to all.

[A] space that all can enter is a space that all can abuse. Each herdsman in seeking to maximize her gain adds one more head of cattle, since the benefit of having one more of her cows grazing in the commons accrues to her alone, whereas the negative consequences of overgrazing must be borne equally by everyone. In the end, though, with each person trapped in this logic, the number of cattle grazing goes beyond what the commons can sustain, and the land becomes worthless to everyone. The problem is that while the herdsman feels compelled to increase her herd without limit, she wishes to do it in a world that is limited. No technical solution serves as an exit from this trap. Bigger commons or more resilient strains of grass only forestall the problem. The answer is not to be found in technology alone.

The only way the tragedy can be avoided is for people to change their behavior. Destruction of the commons is inevitable only so long as people only prize their short-term self-interest. The key is temperance but self-restraint within this context is not only difficult but ultimately ineffectual when it consists in a solitary act alone. What is needed is collective recognition of the mutual benefit of the commons, a genuine willingness on behalf of everyone to make the necessary sacrifice to secure the common good, and a general programme of action for everyone to follow. In other words, there need to be guidelines; for the promise of the commons to be fulfilled, there have to be laws.