Almost 20 years ago Thomas Gilovich wrote a very interesting book about the “Fallibility of Human Reason in Everyday Life” explaining some of the mechanisms through which we tend to deceive ourselves and each other.

In this article, I will use some of his insights to analyze the Anthropogenic Global Warming (AGW) theory. Our collective beliefs on this topic have so important consequences that we cannot allow ourselves to be deceived. If human carbon emissions are really overheating the globe, the costs of not believing this and not acting accordingly, could be catastrophic. Likewise, if carbon emissions have little or no impact on climate, but we are convinced that they do and thus impose draconian measures to reduce energy consumption, we could unnecessarily keep millions of people in poverty for decades. Personally, I wouldn’t want to be wrong in either direction.

Both this winter and the last have been unusually cold in many parts of the globe, with many cold records and snow records being recorded (1). However, it would be incorrect to conclude that the AGW theory is wrong just because a few years of data are not cooperating with the theory. Likewise, it would be erroneous to consider any heat record and extreme weather event as proof of AGW. According to Gilovich, one of our main fallacies is our tendency to conclude “too much from too little” or, in other words, “misinterpreting incomplete and unrepresentative data.”

A prime example of “concluding too much from too little” is Michael Mann’s (2) conclusion of unprecedented warming in the late 20^th century based on a flawed principal component analysis of unrepresentative tree ring data. Basically, the algorithm used would mine the data for series with a hockey-stick shape and give almost all the weight to these series in the final temperature reconstruction. If the algorithm was fed random numbers, it would have generated a hockey-stick in 99% of the cases. As it happens, there were a few bristlecone pine series in California which showed an upward trend towards the end of the period, and these were enough to generate the famous hockey-stick, even though the scientists who originally created and analyzed this data warned that they could not be used as climate proxies. Without those Californian bristlecone series, the hockey-stick graph cannot be generated, and anyway, it would be wrong to suggest global warming, if the only evidence of it comes from an unusual stand of bristlecone pines in California while tree rings from the rest of the World do not suggest a hockey-stick shape (3). It is perhaps even worse that the IPCC singled out this flawed study to support the AGW theory, despite countless other studies of tree-rings, ice-cores and ocean sediments indicating that late 20^th century warming was not unusual in a historical perspective (4).

Even with overwhelming statistical evidence against the AGW theory, a very large share of the World population has come to believe it. Gilovich discusses three “Motivational and Social Determinants of Questionable Beliefs.” The first is “Seeing What We Want to See” which is a well-established psychological mechanism. In the case of AGW it is quite easy to understand why researchers would tend to focus on the bits of evidence in favor of AGW and ignore the majority of evidence against it, because both publication and funding opportunities have favored positive evidence. The media has also been biased in this direction, since catastrophic climate change sells much better than just normal climate variability. The second motivational and social determinant explains why the public at large has also come to believe it, even if they have no clear reason for wanting to see AGW evidence. This mechanism is “Believing What We Are Told.” If both scientists and media repeatedly tell us AGW is true, then we would naturally come to believe in it.

The third motivational and social mechanism is “The Imagined Agreement of Others” or the “False Consensus Effect,” which has been exploited to the fullest by proponents of the AGW theory. They have repeatedly claimed that there is now a scientific consensus in favor of the AGW theory, that only a handful of scientists dissent from this view, and they have compared skeptics to holocaust deniers, heretics, or worse, who should be prosecuted for crimes on humankind (5). However, even if it is risky to be a skeptic, more than 650 scientists (many of them former IPCC contributors) have now come forward publicly to say that they do not believe in the AGW theory, demonstrating that the consensus is indeed imaginary (6).

While erroneous beliefs can sometimes be comforting and useful, this does not seem to be the case with the AGW theory. We ought to be much better at objectively analyzing the data and reporting the results, and avoiding falling into all the above-mentioned traps. Gilovich suggests that the way forward is more widespread social science education, as this kind of training teaches us the necessary habits of mind to analyze messy, complex phenomena like the climate and its effects on human development.

The challenge of teaching people to think critically, instead of mindlessly memorizing and repeating imparted information, is a daunting one, and to be honest, I think the AGW theory will have proven itself wrong long before we manage to get people to think clearly and critically.