Freedom in a commons brings ruin to all.

Every plausible policy must be followed by the question 'And then what?'

In a finite world this means that the per capita share of the world's goods must steadily decrease.

The rational herdsman concludes that the only sensible course for him to pursue is to add another animal to his herd. And another; and another . . . But this is the conclusion reached by each and every rational herdsman sharing a commons. Therein is the tragedy. Each man is locked into a system that compels him to increase his herd without limit — in a world that is limited. 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.

In the specific case of abortion, the matter is particularly easy in that no woman wants a late abortion. Once abortion was made legal, the age of the aborted fetus went down. The slope slipped in the other direction. If we legalize RU-486 and other similar new drugs, the age will fall to one week or less and start approaching zero. The slippery slope will slide in the other direction. The only reason we have late abortions is because we make early abortion difficult.

In an approximate way, the logic of commons has been understood for a long time, perhaps since the discovery of agriculture or the invention of private property in real estate.

Moreover, the practical recommendations deduced from ecological principles threaten the vested interests of commerce; it is hardly surprising that the financial and political power created by these investments should be used sometimes to suppress environmental impact studies.