For those who are just discovering this series, welcome! Here is Monday's edition, which got things started by defining propositions & arguments (now updated!), & here is Wednesday's diary on a few ambiguity fallacies. While I'm going to try to make each part of this series as self-contained as possible, please feel free to review the previous parts & let me know if you have any questions, comments, or suggestions.
This series (which also may be called "Brown Thrasher Sorts Through Logic Books & Notes") is meant as an informal introduction to logical argument that I hope to make into a useful community resource for Daily Kos discussions. Since I myself am not a teacher or professional logician, I welcome suggestions from any professionals in this area as to how to improve this labor of love.
The 1st of several sections on relevance fallacies past the Kos Antique Flourish — & this time, it's getting personal...
On Wednesday I discussed a few ambiguity fallacies — the sort which raise "What" questions by failing to be clear. Today I'll present several relevance fallacies, those raising such questions as "So What" or "Who Cares" by stating what is beside the point. Indeed, most informal fallacies which textbooks list have to do with relevance.
(At this point, I ought to mention once again one of the differences between informal & formal logic: Ambiguity or irrelevance do not necessarily mean falsehood. A statement may be a lie or the truth, but if it has nothing to do with the matter at hand, claiming it does is a fallacy.)
Today I'll list a family of fallacies which we who visit political blogs generally encounter sooner rather than later. Its Latin name is "Argumentum Ad Hominem", meaning "argument at the man", & many people call it the Genetic Fallacy. In everyday talk, though, you've probably most often heard it called the Personal Attack. These fallacies turn attention to the source of an argument rather than whether the argument works on its own merits. (Also note, especially in the 1st case, that "attack" does not always mean "insult". I'm using it in the more general sense of "attacking an argument from a personal angle".)
Abusive Personal Attack.
While obvious, direct insults can be used in this manner ("That's the sort of argument I'd expect from someone like you..."), anything that inappropriately drags someone's character or characteristics into the argument falls into this category ("Surely as a Catholic you see that I am right." "How can you possibly agree with him? You're [insert nationality here]!" (& so on...))
Circumstantial Personal Attacks.
Abusive & circumstantial forms of personal attack can sometimes look very similar to each other, but attacks based on circumstances mostly concern a person's situation. Texts & popular sources usually list 2 broad types:
The You-Too (Latin: tu quoque) fallacy takes many forms — "You do it too", "You're one to talk", even misapplications of "Practice what you preach" & "Glass houses" — but all of them dodge an argument's merits by focusing on where an arguer is, what an arguer does, an arguer's usual company, & other such things. (Familiar political examples: "You can't complain; you Dems would do the same if you were in power." "If you want cheap health care, why haven't you moved to Canada?")
Though the fallacy itself is likely even older, the expression "Poisoning The Well", according to Wikipedia, refers to a retreating army using the "scorched-earth" tactic of fouling fresh-water sources with toxins in order to make them useless to an approaching enemy. Thus, someone committing this fallacy tries to pre-empt the believability of an opponent's argument by ascribing it to a hidden agenda, inherent bias, cynical self-interest, or whatever the case may be ("Anyone who disagrees is either an idiot, a liar, or a shill." "How lousy you must be at your job not to recognize my brilliance.")
This family of fallacies has great power to derail discussions — a large part of the reason why online discussion boards tend to frown upon people calling each other "shills" & "trolls" without enough evidence to back such assertions. Another thing to keep in mind: They can be used to "defend" as well as "attack" an argument, but are just as faulty either way they are used.
Also, the words & insinuation that people use in personal fallacies frequently beg the question & use circular definitions — but more about that later...