The Magazine

The Icarus Syndrome

Should we pay any price to avoid the consequences of global warming?

Sep 8, 2008, Vol. 13, No. 48 • By JIM MANZI
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One could argue that we should therefore push down carbon dioxide emissions far faster than the odds-adjusted risk of global warming costs appear to justify. How much faster? One widely discussed benchmark for a "safe" level of emissions is to set a target limit for atmospheric concentration of CO2 of no more than 150 percent of its current level. Suppose we did this via what most economists believe is the most efficient imaginable means: a globally harmonized and perfectly implemented worldwide tax on carbon. According to the modeling group led by William Nordhaus, a Yale professor widely considered to be the world's leading expert on this kind of assessment, we, humanity, could expect to spend about $17 trillion more under such a regime than the benefits that we would expect to achieve. To put that in context, the annual GDP of the United States of America is about $13 trillion. That's a heck of an insurance premium for an event so unlikely that it is literally outside of a probability distribution. But I can find major public figures who say that this level of atmospheric carbon dioxide is still too dangerous. Al Gore has proposed an even lower target for emissions that if implemented through an optimal carbon tax is expected to cost more like $23 trillion in excess of benefits. Of course, even this wouldn't eliminate all risk, and I can find highly credentialed scientists who say we need to reduce emissions even faster. Once we leave the world of odds and trade-offs and enter the Precautionary Principle zone, there is no nonarbitrary stopping point. We would be chasing an endlessly receding horizon of zero risk.

But to force massive change in the economy based on such a fear is to get lost in the hothouse world of single-issue advocates and become myopic about risk. We face lots of other unquantifiable threats of at least comparable realism and severity. A regional nuclear war in central Asia, a global pandemic triggered by a modified version of the HIV virus, or a rogue state weaponizing genetic-engineering technology all come immediately to mind. Any of these could kill hundreds of millions of people. Specialists often worry about the existential risks of new technologies spinning out of control. Biosphere-consuming nano-technology, supercomputers that can replace humans, and Frankenstein-like organisms created by genetic engineering are all topics of intense speculation. Sometimes, though, we face monsters from the deep: The cover of the June Atlantic Monthly said of the potential for a planet-killing asteroid, "The Sky Is Falling!"

A healthy society is constantly scanning the horizon for threats and developing contingency plans to meet them, but it's counterproductive to become paralyzed by our fears. The loss of economic and technological development that would be required to eliminate all theorized climate change risk or all risk from genetic and computational technologies or, for that matter, all risk from killer asteroids would cripple our ability to deal with virtually every other foreseeable and unforeseeable risk, not to mention our ability to lead productive and interesting lives in the meantime. The Precautionary Principle is a bottomless well of anxieties, but our resources are finite.

In the face of massive uncertainty, hedging your bets and keeping your options open is almost always the right strategy. Money and technology are the raw materials for options. The idea of the simple, low-to-the-ground society as more resilient to threats is, like the story of Icarus, a resonant myth. But experience shows that wealthy, technologically sophisticated societies are much better able to withstand resource shortages, physical disasters, and almost every other challenge than poorer societies.

Consider that if a killer asteroid were actually to approach the Earth, we would rely on orbital telescopes, spacecraft, and thermonuclear bombs to avert disaster. In such a scenario, we would be very glad that we hadn't responded to the threat of peak coal back in the 1860s by slowing our development to such an extent that we lacked one of these technologies. In the case of global warming, a much more appropriate approach than rationing energy and forgoing trillions of dollars of economic growth is to invest a fair number of billions of dollars into targeted scientific research that would give us technical alternatives if a worst-case scenario began to emerge.

We should be very cautious about implementing government programs that require us to slow economic growth and technological development in the near-term in return for the promise of avoiding inherently uncertain costs that are projected to appear only in the long-term. Such policies conceal hubris in a cloak of false humility. They inevitably demand that the government coerce individuals in the name of a nonfalsifiable prediction of a distant emergency. The problem, of course, is that we have a very bad track record of predicting the specific problems of the far future accurately.

We can be confident that humanity will face many difficulties in the upcoming century, as it has in every century. We just don't know which ones they will be. This implies that the correct grand strategy for meeting them is to maximize total technical capabilities in the context of a market-oriented economy that can integrate highly unstructured information into prices that direct resources, and, most important, to maintain a democratic political culture that can face facts and respond to threats as they develop.

Jim Manzi is chief executive officer of an applied artificial-intelligence software company.