Falacious reasoning

In order to understand what a fallacy is, one must also understand the difference between validity and truth. A fact can be true or false, but only an argument can be valid or invalid. Fallacies have to do with false arguments, not false facts. Likewise, one can tell a lie without committing a fallacy, although it is also possible to do both at the same time.

The world is full of fallacies. They are uttered on a daily basis, quite often by politicians, lawyers, religious people, advertisers, and anyone who wishes to persuade someone to do or accept something on the basis of believing a reasoned argument. However, if the targets of persuasion were able to see that an argument was flawed, or fallacious, they might not be taken in. It is therefore useful to be able to spot fallacies when they are used, and to be aware that one might be committing one when the boot is on the other foot.

Fallacies are dangerous because they can so easily be confused with statements of fact. One frequently heard argument, for example, is that somebody in public esteem must have committed an indiscretion based on the strength of rumours currently circulating. The argument used is: “There’s no smoke without fire”. That may or may not be true, and the person in question may or may not be guilty of the act in question, but the argument used is faulty. The fallacy lies in the inappropriateness of applying the facts about smoke and fire to a situation in which unsubstantiated accusations spread via the grapevine (and newspaper tittle-tattle) and are taken as being true simply because they are frequent and insistent. There may not be smoke without fire, but there can certainly be false accusations without any grounding in reality.

Undistributed middles

Politicians frequently fall for the argument that “something must be done”. A bad situation has arisen and a solution must be found. Action is taken and justified with the line mentioned above. This is often taken as sound enough argument, but it is a fallacy. The argument could be expanded as: “Something must be done. This is something. Therefore it must be done”.

Such an argument might sound persuasive until one substitutes other terms in a similar argument. For example: “My cat drinks water. My dog drinks water. Therefore my cat is a dog”. This is known technically as the “fallacy of the undistributed middle”, because the significance of the middle term of the argument has not been appreciated as being applicable to other circumstances. Yes, my dog does drink water, but then so do plenty of other animals, and one could just as easily argue, on this basis, that my cat is a buffalo or a chimpanzee.

The absurdity of the cat/dog argument is obvious to anyone, which is why the same reasoning needs to be applied to “something must be done”. Yes, the proposed course of action is “something”, but there are plenty of other “somethings” that would be just as reasonable if offered as potential policies. People need to be more aware of the rhetorical tricks that politicians play, because they are often based on reasoning that is just as fallacious as this.

A prime example of the “undistributed middle” fallacy was its use by Senator Joseph McCarthy during the “UnAmerican” witch hunts of the 1950s, when proof was sought that people in the public eye were Communists. This took the form, for example, of: “Here is a man who disapproves of racial discrimination. Communists disapprove of racial discrimination. Therefore this man is a Communist”. The fact of whether or not this is true is neither here nor there; the man might indeed be a Communist but this reasoning is not proof of that fact, because it is perfectly possible to be against racial discrimination and not be a Communist. It is important to realise that the fact that the reasoning is fallacious only negates the validity of the argument and not its truth, because the two are entirely separate.

Many questions

Although a fallacy can be defined as a faulty argument, the way it is presented may come across in another way, for example as a question. One such, which is often asked in a religious context, is: “What is the purpose of human life?” The fallacy involved here is known as “The fallacy of many questions” because it purports to be one question but is really much more than that. When it is asked of someone, the questioner is implying the question “What is the purpose of your life?”, and the same would apply whenever they asked it of anyone else. Every time it is asked it is a different question and may therefore get a different answer, each of which could be equally valid. However, by phrasing it in general terms the implication is that there is only one answer, which is of course the one that the questioner wants everyone to accept, whereas the question could only be valid if it sought to ascertain a purpose for every live individual, each of whom would have to be asked and for all their answers to be taken into account.

In this latter case, the questioner cannot be accused of lying to the person being questioned, because no assertion has (at this stage) been made, but they can be held guilty of using fallacious reasoning because of the nature of the tactic they are employing. It is a trick used countless times, not only in the sphere of religion but by politicians and the whole range of snake-oil salesmen who rely on the gullibility of their audience.

There are many types of fallacy that have been recognized and named, some notable ones being the Naturalistic Fallacy (which claims that anything that occurs naturally must be inherently good) and the Pathetic Fallacy (which ascribes human characteristics to natural objects).

In all cases, a fallacious argument is one that is not necessarily without basis in fact, as it might well so have, but it has no basis in logic. It is therefore often more convincing to defeat an argument by proving it to be fallacious than to seek to show it up as factually inaccurate or advancing an untruth. Fact and truth can be argued both ways, but there is no gainsaying of logic.

© John Welford