by Tim Harding
Fallacies are patterns of reasoning that are logically incorrect. They apply to arguments rather than isolated statements or propositions. Arguments are logically valid or invalid, whereas propositions are true or false. The fallacies of relevance, for example, clearly fail to provide adequate reason for believing the truth of their conclusions. Although they are often used in attempts to persuade people by non-logical means, only the unwary, the predisposed, and the gullible are apt to be fooled by their illegitimate appeals. Many of them were identified by medieval and renaissance logicians, some of whose Latin names for them have passed into common use. It’s worthwhile to consider the structure, offer an example, and point out the invalidity of each of them in turn. [i]
I have previously talked here at the Mordi Skeptics about three fallacies of relevance:
- Appeal to Popularity (argumentum ad popularum)
- Appeal to Authority (argumentum ad verecundiam)
- Argument from Personal Abuse (argumentum ad hominem)
I would now like to briefly talk about three more fallacies of relevance:
Appeal to Pity (argumentum ad misericordiam)
An Appeal to Pity tries to win acceptance by pointing out the unfortunate consequences that will otherwise fall upon the speaker and others, for whom we would then feel sorry.
P1: I am a single parent, solely responsible for the financial support of my children.
P2: If you give me this traffic ticket, I will lose my licence and be unable to drive to work.
P3: If I cannot work, my children and I will become homeless and may starve to death.
C: Therefore, you should not give me this traffic ticket.
The conclusion may be false (that is, perhaps I should be given the ticket) even if the premises are all true, so the argument is fallacious.
Appeal to Force (argumentum ad baculum)
Turning this on its head, in the Appeal to Force, someone in a position of power threatens to bring down unfortunate consequences upon anyone who dares to disagree with a proffered proposition. Although it is rarely developed so explicitly, a fallacy of this type might propose:
P1: If you do not agree with the Government’s position, we will cut funding for your scientific research.
P2: The Government’s position is that cattle grazing in alpine national parks reduces bushfire risk.
C: Therefore, cattle grazing in alpine national parks reduces bushfire risk.
Again, it should be clear that even if all of the premises were true, the conclusion could nevertheless be false. Since that is possible, arguments of this form are plainly invalid. While this might be an effective way to get you to agree (or at least to pretend to agree) with the Government’s position,[ii] it offers no grounds for believing it to be true.
Guilt by association (a type of ad hominem argument)
Guilt by Association relies upon emotively charged language to arouse feelings and prejudices that may lead an audience to accept its conclusion:
P1: As all clear-thinking residents of our fine state have already realized, opposition to cattle grazing in alpine national parks is nothing but the dangerous deluded dingo of greenie anti-farming propaganda cleverly disguised in the harmless sheep’s clothing of science.
C: Therefore, banning cattle grazing in alpine national parks is bad public policy.
The problem here is that although the flowery language of the premise might arouse strong feelings in many members of its intended audience, the widespread occurrence of those feelings has nothing to do with the truth of the conclusion.
[ii] Of course, public servants are required to implement lawful Government policy whether they agree with it or not; but scientists are supposed to provide independent scientific advice.