MATT RIDLEY: Relax: The World’s Resources Aren’t Running Out.

I have lived among both tribes. I studied various forms of ecology in an academic setting for seven years and then worked at the Economist magazine for eight years. When I was an ecologist (in the academic sense of the word, not the political one, though I also had antinuclear stickers on my car), I very much espoused the carrying-capacity viewpoint—that there were limits to growth. I nowadays lean to the view that there are no limits because we can invent new ways of doing more with less.

This disagreement goes to the heart of many current political issues and explains much about why people disagree about environmental policy. In the climate debate, for example, pessimists see a limit to the atmosphere’s capacity to cope with extra carbon dioxide without rapid warming. So a continuing increase in emissions if economic growth continues will eventually accelerate warming to dangerous rates. But optimists see economic growth leading to technological change that would result in the use of lower-carbon energy. That would allow warming to level off long before it does much harm.

Just look at how the fracking boom has undercut claims that we had passed “Peak Oil.” You don’t hear the “peak oil” phrase any more, and yet it was on everyone’s lips a decade ago.