But they dont. The reasons why they dont, and why the environment has not been ruined, have to do with prices, technological innovation, social change and government regulation in response to popular pressure. That is why todays environmental problems in the poor countries ought, in principle, to be solvable.
Raw materials have not run out, and show no sign of doing so. Logically, one day they must: the planet is a finite place. Yet it is also very big, and man is very ingenious. What has happened is that every time a material seems to be running short, the price has risen and, in response, people have looked for new sources of supply, tried to find ways to use less of the materials, or looked for a new substitute. For this reason prices for energy and for minerals have fallen in real terms during the century. The same is true for food. Prices fluctuate, in response to harvests, natural disasters and political instability; and when they rise, it takes some time before new sources of supply become available. But they always do, assisted by new farming and crop technology. The long-term trend has been downwards.
It is where prices and markets do not operate properly that this benigntrend begins to stumble, and the genuine problems arise. Markets cannot always keep the environment healthy. If no one owns the resource concerned, no one has an interest in conserving it or fostering it: fish is the best example of this.
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