Fallacy recognition and reasoning skills development

Fallacy Hunt

Logical fallacies are frequently seen in everyday life. This paper will examine some recent examples of logical fallacy to help shed light about what types of fallacies exist and how they are being used. By identifying fallacies, we can better prepare ourselves to win debates, understand when someone is not making a strong case, and better understand the tools that people use to mislead us.

The first fallacy, as recorded in print in the New York Post, was the claim that U.S. secret agents had infected Hugo Chavez with cancer. Such an argument is a false dilemma.

We know that Hugo Chavez died from cancer. We do not know the root cause of the cancer, if such a thing can even be determined. This argument therefore rests on the idea that there are two options available, that the cancer was natural or that the U.S. gave him cancer. The natural option is unmentioned, but implied. Its removal is then implied, without any reason for its exclusion. This leaves the sole remaining option as the U.S. having given him the cancer. There are certainly elements of the appeal to ignorance here as well, in that nobody knows for certain where the cancer came from. This lack of proof is implied as lending credence to the alternate proposition (U.S. gave him cancer). By combining two fallacies, the argument is presented, but the structure of the argument is rooted in a false dilemma.

The second fallacy comes from Rand Paul's filibuster in the Senate this past week. The filibuster is a 13-hour speech in opposition of the nomination of John Brennan to the post of CIA chief. The logical fallacy is the slippery slope. At the outset of the filibuster, Paul begins with the proposition that Brennan (and the President) have authorized the use of drones to kill enemy combatants. His second proposition is that they have not denied explicitly that they will use drones on U.S. citizens on U.S. soil. The third proposition is that there is a high likelihood that they will do so. The conclusion therefore is that John Brennan should not be head of the CIA. The case against Brennan rests in large part on the actions (or lack thereof) of the President, itself a logical fallacy. However, the slippery slope occurs because the objection Paul is raising is the third proposition, that there will be attacks on American citizens on American soil, something to which he strenuously objects. In this, he is objecting to a theoretical action that has not taken place, but that he imagines will take place because of his belief in the first two propositions. Regardless of what one thinks about the first two propositions, the third is conditional, and it is this condition to which he objects, hence the slippery slope logical fallacy.

The third fallacy comes from an Internet article, a blog post by Paul Knappenberger and Patrick Michaels at the Cato Institute. They write in relation to the snowstorm in Washington, DC this past week, and discuss the issue of climate change. Their proposition is that "all events fall within their natural characteristics," referring to weather events. They even follow this up with "The null hypothesis is a tough one to overturn." The logical fallacy at work here is a hasty generalization, combined with the appeal to ignorance. The structure follows the hasty generalization. The premise is that some weather events are "within their natural characteristics." The conclusion is that this event - and all others -- should also be considered within their natural characteristics. The generalization is not warranted because it is based on an appeal to ignorance argument -- that if we do not know for certain that climate change was involved in a weather event we should assume that it was not involved. Since there are mitigating factors, it is impossible to tell for certain if any one given weather event is caused by climate change, and the evidence commonly presented in support of climate change never rests on a single weather event, so there is a straw man here as well.

The fourth fallacy comes from a comment made by a friend, arguing that "The TSA doesn't know what it's doing" and citing as evidence "Pocket knives are okay, but water bottles are not?" This is a false analogy. The pocket knife is the thing; the water bottle is the thing to which it is compared. (Or more precisely, the TSA policy with respect to these objects). The implication in the argument is that these objects are analogous because they were both previously banned from airplane cabins. The conclusion that the TSA doesn't know what it's going stems from the fact that the TSA now treats these two items differently. The things are not analogous, however, because they are banned for different reasons. The argument would have been stronger if the comparison object was a boxcutter, something that is still banned. However, the water bottle (from outside security) is not a cutting object and is banned for somewhat different reasons.