Fallacies – A
Commonplace Book – Pages 89-91 – 93-95
Fallacy of Accent: A written word could be ambiguous in a way that depended on how it was accented in speech. That is, some words are homographs but not homophones. Example: ‘resent’
Fallacy of Accident: a.k.a. ‘A dicto simplicitor ad dictum secundum quid‘ – Occurs when one either attempts to apply such a rule of thumb to an obviously abnormal instance, or when one treats the rule itself as if it were an exceptionless universal generalization, rather than a defensible rule of thumb.
Affirming the Consequent: Arguments of this form are invalid. Informally, it means that arguments of this form do not give good reason to establish their conclusions, even if their premises are true. Example: ‘If P, then Q. Q. therefore, P.’
Affirmative Conclusion from a Negative Premise: Any form of categorical syllogism with an affirmative conclusion and at least one negative premise. Example: ‘All judges are politicians. Some lawyers are not judges. Therefore, some lawyers are politicians.’
Affirming a Disjunct: A non-validating form of argument when ‘or’ is inclusive, as it is standardly interpreted in prepositional logic. But in order to accuse an argument of committing this fallacy, we must determine in which sense the ‘or’ in the first premise is used.
Ambiguity: A a feature of language, ambiguity occurs when a word or phrase has more than one meaning. As a logical fallacy, Ambiguity occurs when linguistic ambiguity causes the form of an argument to appear validating when it is not.
Ambiguous Middle: Any valid form of categorical syllogism with an ambiguous middle term. A categorical syllogism is an argument with three categorical terms occurring within it. ‘Term’ is to be understood in a semantic sense, so that a single word may ambiguously stand for two terms. This leads to the possibility of ambiguous syllogisms in which one of the words equivocates on two terms.
Amphiboly: Linguistically, an amphiboly is an ambiguity which results from ambiguous grammar, as opposed to one that results from the ambiguity of words or phrases. The fallacy of Amphiboly occurs when a bad argument trades upon grammatical ambiguity to create an illusion of cogency. Example: ‘The panda eats, shoots, and leaves.’
The Anecdotal Fallacy: The Availability Heuristic. ‘The easier it is to remember a type of event, the more likely it is that an event of that type will occur.’ However this leads to fallacies as unusual events do happen. The fallacy is using a recent memory, unusual event or a striking anecdote to lead one to overestimate the probability of events of that type occurring.
Argument by Consensus: ‘Argumentum ad Populum‘ – ‘Idea A is popular, therefore idea A is correct.’ It is committed whenever one argues for an idea based on an irrelevant appeal to its popularity.
Appeal to Misleading Authority: ‘Argumentum ad Verecundiam‘ – We often rely upon expert opinion when drawing conclusions about technical matters where we lack the time or expertise to form an informed opinion. Experts are human beings, after all, and human beings err. This is why on major matters, you should get a second or even third opinion.
Appeal to Celebrity: Since most celebrities are actors or sports stars, they are seldom experts on the products or causes that they endorse. Another problem is that most celebrities who endorse products are paid to do so, and thus the endorsement is not a disinterested one.
Appeal to Consequences: ‘Argumentum ad Consequentum‘ – Arguing that a proposition is true because belief in it has good consequences, or that it is false because belief in it has bad consequences is often an irrelevancy. One can tell that the fallacy is being committed because the consequences do not follow from the proposition itself, but only from belief in it. Example: A child’s belief in Santa may have good consequences, but this has nothing to do with whether there really is a Santa.
Appeal to Force: ‘Argumentum ad Baculum‘ – As a logical fallacy, it applies to the use of force and, by extension, the use of threats of force to ‘win’ a debate. Attempts to change people’s minds by threats are appeals to consequences, since the bad consequences appealed to are not consequences of what is believed, but of the belief itself. Also force used to suppress the arguments of one side in a debate, that is a type of -one-sidedness.
Appeal to Ignorance: ‘Argumentum ad Ignorantiam‘ – ‘There is no evidence against P. Therefore, P.’ An appeal to ignorance is an argument for or against a proposition on the basis of a lack of evidence against or fot it. If there is positive evidence for the conclusion, then of course we have other reasons for accepting it, but a lack of evidence by itself is no evidence.
Appeal to Nature: ‘Argumentum ad Naturam‘ – The problem is that the concept of nature is vague. The vagueness of the notion of naturalness does not mean that it is useless, since there are many clearcut cases of the natural and unnatural. However, an appeal to nature which is based on a borderline case will be unsound because it will be unclear whether its premise is true or false. Sometimes, people associate ‘natural’ with ‘good’ and this is a fallacy. To treat the rule of thumb as if it were an exceptionless generalization is to commit a fallacy.
Argument Against the Man: ‘Argumentum ad Hominem‘ – A debater commits this fallacy when he/she introduces irrelevant personal premises about his opponent. Such attacks may successfully distract the opponent or audience from the topic of the debate.
Argument of the Beard: This is based upon the claim that a controversial type of action will lead inevitably to some bad type of action. The argument is by no means fallacious, but the strength of the argument is inversely proportional to the number of steps between A and Z, and directly proportional to the causal strength of the connections between adjacent steps. If there are many intervening steps, and the causal connections between them are weak or unknown, then the resulting argument will be weak or fallacious.