by Tom Harris, ©2021
(Sep. 3, 2021) — Missing from most, if not all, coverage of last month’s climate science report from the United Nations Intergovernmental Panel on Climate Change (IPCC) was the fact that their most important conclusions are impossible; not merely contested or exaggerated, but literally impossible.
Consider the following from the IPCC full Working Group I report, Climate Change 2021: the Physical Science Basis, issued on August 9:
“Warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising global average sea level.”
It is obviously a mistake to refer to “global average air and ocean temperatures…and global average sea level” as “observations.” They are the results of statistical manipulations of thousands of observations in different places and at different times.
But, more significantly, the idea that any of the science conclusions of the IPCC are “unequivocal,” or, as Al Gore often asserts, “truth,” is irrational.
Plato defined truth as something that is universal, necessary, and certain.
It is universal in the sense that it applies everywhere. Whether you are in Athens, Sparta or on another planet, it is true. It also applies “everywhen,” now, in five minutes or in a billion years.
Truth is also necessary. It must be the way it is; there is no other explanation possible. It is unequivocal.
And truth is certain. It is not a matter of probability. It is in the bank.
Truth applies to things like mathematics or chess in which we write the rules. Two plus two equals four. The Queen can move vertically, horizontally or diagonally in a straight line around the chess board, as long as no pieces are obscuring her path. Those statements are true and unequivocal.
But truth never applies to our findings about nature, which are educated opinions based on scientists’ interpretations of observations. And philosophers since ancient times have recognized that observations cannot prove anything to be true. In contrast to being universal, necessary, and certain, empirical evidence is particular, contingent, and has some degree of probability.
So, contrary to the IPCC’s confident pronouncement, observational evidence cannot be used to prove anything to be true or unequivocal. Not only are our methods of observing imperfect but we all have biases that affect how we interpret what we see.
Indeed, all scientific hypotheses, and even scientific theories, are never truth or unequivocal; they can be, and often are, wrong. Science “facts” are merely the current opinions of experts, and, especially in the case of climate change, different experts often have very different points of view. For example, the Climate Change Reconsidered series of reports of the Nongovernmental International Panel on Climate Change (NIPCC) summarize thousands of studies from peer-reviewed scientific journals that either refute or cast serious doubt on the IPCC’s science. So contrary to being unequivocal, there are many possible scientific explanations for the modest warming of the past century.
Consider the following feedback about the IPCC’s use of the word “unequivocal” from two philosophers.
Lehigh University philosophy professor Steven Goldman supports the dangerous human-caused global warming hypothesis but explained in a personal communication that such IPCC statements are flawed. It is “an attempt to persuade extra-logically,” said Goldman. “Strictly logically, no observations can lead to an ‘unequivocal’ interpretation.”
David Wojick, a Virginia-based Ph.D. in the logic and philosophy of science, disagrees with Goldman about the climatic impact of human activity but agrees that the IPCC makes a serious mistake here. “Reasoning from evidence is inductive logic,” said Wojick. “As for unequivocal, that is never the case in inductive logic.”
It wouldn’t be quite so bad if the IPCC’s use of “unequivocal” was limited to this single quote. But the word appears a total of 32 times in the full report. And this mistake appeared regularly in past IPCC reports as well as in statements from IPCC leaders.
***So why do more philosophers not speak out about these problems, errors that are diverting the public from properly considering the various arguments presented? It may be that academics judge that acceptance of climate concerns will encourage pollution reduction, alternative energy development, conservation, increased foreign aid, and social justice, things many regard as beneficial. So, they keep their opinions to themselves rather than risk impeding progressive policies.
But when authorities preach truth about science, progress stops. Albert Einstein once said,
“Whoever undertakes to set himself up as a judge of truth and knowledge is shipwrecked by the laughter of the gods.”
It might be humorous to the gods, but the belief that we know the “truth” about climate change and that the science is unequivocal has resulted in over one billion U.S. dollars a day being spent trying to “stop climate change.” Imagine what could done if such vast sums were instead dedicated to education, health care, cleaning up our rivers, or adapting to the inevitable natural environmental changes that lay ahead.
It’s time to open up the scientific debate about climate change, one of the most complex and costly issues of our age.
Tom Harris is executive director of the non-partisan Ottawa, Canada-based International Climate Science Coalition.