"Looking at any graph of CO2 and temperature over time, we can see that there is undoubtedly a correlation between the two. As the former increases, so does the latter. This is undeniable proof that anthropogenic increases in carbon dioxide are leading to a dramatic and unprecedented increase in temperature . This temperature increase will lead to 20 foot rises in sea level due to the melting of the icecaps, mass extinctions, climate refugees, new and deadlier diseases, leading to a world that is uninhabitable for our future generations . There is now a scientific consensus that global warming is due to anthropogenic emissions of carbon dioxide, a deadly pollutant [3,4]. The volume of peer reviewed literature casts no doubt on the matter [5,6,7]. The small minority who wishes to distract from the issue with claims that global warming is not real are shills funded by the oil industry ."The purpose of the above paragraph is that what is seen there is commonly what one will find peppered about from the side defending AGW. Usually, the rhetoric steps away from the science, and instead moves into a largely political realm, bastardizing something that should be largely an issue of scientific accuracy and precision (thank you, Al Gore and the media). In fact, the lay person with no scientific background will not even understand the true science and concerns behind the issue, but will instead focus on the points above to make their case.
So why is that a problem, you may ask? The reason is that each of the numbered statements above is a logical fallacy. Logical fallacies are errors in reasoning in an argument which render the entire argument invalid. These fallacies may arise from a lack of critical thinking on the part of those committing the fallacy, as in a student who wishes to make a case in a paper. They can also arise on purpose, usually from politicians who wish to use the logical fallacy in a debate, hoping to appeal to the audience and “win” the debate (yes, I realize that any references to logic and politicians should remain at arm’s length at all times).
Below I will point out what it is that makes these arguments fallacious.
: Temperature increases as CO2 increases. Therefore industrialization is causing global warming.
This fallacy is commonly known as cum hoc ergo propter hoc, or “with this, therefore because of this.” It is the fallacy of correlation, the need of human psychology to automatically see connections where they may not or only weakly exist. A common statement is “correlation does not imply causality.” This is not to say that two seemingly correlated variables are not related, it is only to say that we cannot look at the correlation and claim to know that one causes the other. Often, the relationship may be spurious, with other confounding factors. To claim complete knowledge of a complex system based on one graph is foolish, to say the least.
: We are dooming the world, and millions will die now and in the future.
This is commonly referred to as the argumentum ad metum, or the appeal to fear. This is where an arguer attempts to exploit the fears of the audience in order to get them agreeing to their proposal. As an argument, it is logically invalid, as appealing to an emotion does not prove the argument itself. The statement could be made to argue for anything, as follows: A: We should either federally mandate health insurance, or allow people to choose to not have it.B: Without health insurance, millions of people will not be able to get operations, tens of thousands of newborns will die because they will not have medical care,…, and life will be miserable in general. C: Therefore, we should mandate health insurance.
: There is a scientific consensus regarding our CO2 emissions in regards to global warming.
I will disregard completely the problems inherent in trying to claim that there is a scientific consensus. For anyone who wants to understand philosophically how science should work, I refer you to Karl Popper. The real problem with this statement is the fact that it is known as an appeal to authority. We are told that 2500 scientists agree with the IPCC statement that we are causing irreversible global warming. Forgetting the mounting evidence that the 2500 number may not be so grandiose, the fact still remains that simply because a large number of “authorities” on a subject agree, it does not in any way prove said subject to be correct.
: The warming seen by the planet is undoubtedly caused by Carbon Dioxide.
Climate is an incredibly complicated system (coupled & nonlinear, for you math geeks out there) that is, considering the global ups and downs of temperature that have both preceded and postceded (yes, I made that word up) the existence of mankind, driven by many factors which all have a deep coupling that we have yet to thoroughly understand. So we are led to the fallacy of the single cause. This fallacy occurs as an attempt to determine a single, simple cause to a complex problem, which often leads to the minimalization of the other potential causes.
: Hundreds, nay, thousands of peer reviewed papers prove the link between anthropogenic CO2 and global warming.
While the fallacy that I am about to point to is not (yet) a fallacy per se, I definitely think that it belongs in any list that wishes to present faulty reasoning. This fallacy is known as the Fallacy of Peer Review. I prefer to entitle it “Publication Snobbery,” in a vain attempt to position myself as being on par with C.S. Lewis (who coined the phrase “Chronological snobbery”). It is the notion that ideas or research are not worthwhile or valid unless they have been published in a peer reviewed journal (one need only peruse the discussion section of the global warming page on Wikipedia to see how rampant this is). It is a specific form of the appeal to authority seen at . The fallacy is in the belief that because research is peer reviewed, it effectively “proves” something. However, reviewers and editors both have their own cognitive biases, and the simple act of being peer reviewed proves nothing other than the fact that the research was well performed, and that its conclusions follow from its data.
: The volume of literature speaks to the strength of our theory.
This is called Proof by Verbosity. It occurs when one attempts to provide such a volume of information that opponents have no choice but to agree, because there is not enough time in the world to research and disagree. I hate to point to Wikipedia again, but a glance at the reference section in the Global Warming article should cement the concept firmly into one’s head. When combined with an attack using Publication Snobbery, it is surely a formidable foe.
: The volume of literature speaks to the strength of our theory.
In any scientific subject, there will often be papers published in an attempt to prove both sides of a debate. This is why we are constantly bombarded by the media with differing reports on the health effects of certain foods/drugs/drinks/chemicals/etc. These reports come from papers all published by different authors, who wish to prove opposing hypotheses. The same is true with the global warming debate (although the “deniers” have a much more difficult time procuring funding). However, when one chooses to consistently pick data/papers/opinions that correspond to only their stance while disregarding anything that disagrees, we call this Cherry Picking.
: Our detractors are well funded oil industry mouthpieces.
This is perhaps the most common fallacy, known as the argumentum ad hominem. As the name implies (at least to anyone with a rudimentary knowledge of Latin), it is an attack launched against the character of an opponent, rather than the opponent’s position. It is an effective means of attack, especially when the opponent has detestable characteristics. Alas, ultimately, it is logically unfound. A more specified version is known as poisoning the well.
While there is no doubt in my mind that the typical declarations of a global warming believer could be analyzed different, I wanted to make a point that when science is politicized, either by politicians or scientist-activists, it is necessary for people to be able to think critically and disregard arguments that have no logical basis. In fact, this can be said for any debate where one attempts to make an argument using fallacious claims. The logicians out there will probably disagree with this analysis, and I welcome their disagreement, in all shapes and forms.