In the Wall Street Journal, Matt Ridley explains that claims that we’re running out of this or that resource are almost always bogus:
How many times have you heard that we humans are “using up” the world’s resources, “running out” of oil, “reaching the limits” of the atmosphere’s capacity to cope with pollution or “approaching the carrying capacity” of the land’s ability to support a greater population? The assumption behind all such statements is that there is a fixed amount of stuff — metals, oil, clean air, land — and that we risk exhausting it through our consumption.
But here’s a peculiar feature of human history: We burst through such limits again and again. After all, as a Saudi oil minister once said, the Stone Age didn’t end for lack of stone. Ecologists call this “niche construction” — that people (and indeed some other animals) can create new opportunities for themselves by making their habitats more productive in some way. Agriculture is the classic example of niche construction: We stopped relying on nature’s bounty and substituted an artificial and much larger bounty.
Economists call the same phenomenon innovation. What frustrates them about ecologists is the latter’s tendency to think in terms of static limits. Ecologists can’t seem to see that when whale oil starts to run out, petroleum is discovered, or that when farm yields flatten, fertilizer comes along, or that when glass fiber is invented, demand for copper falls.
That frustration is heartily reciprocated. Ecologists think that economists espouse a sort of superstitious magic called “markets” or “prices” to avoid confronting the reality of limits to growth. The easiest way to raise a cheer in a conference of ecologists is to make a rude joke about economists.
In 1972, the ecologist Paul Ehrlich of Stanford University came up with a simple formula called IPAT, which stated that the impact of humankind was equal to population multiplied by affluence multiplied again by technology. In other words, the damage done to Earth increases the more people there are, the richer they get and the more technology they have.
Many ecologists still subscribe to this doctrine, which has attained the status of holy writ in ecology. But the past 40 years haven’t been kind to it. In many respects, greater affluence and new technology have led to less human impact on the planet, not more. Richer people with new technologies tend not to collect firewood and bushmeat from natural forests; instead, they use electricity and farmed chicken — both of which need much less land. In 2006, Mr. Ausubel calculated that no country with a GDP per head greater than $4,600 has a falling stock of forest (in density as well as in acreage).