A logical fallacy is an error in reasoning, an argument with a fatal flaw that makes its logic invalid. Philosophers have categorized and defined numerous logical fallacies, some of which are profiled in this essay. When taking part in a debate (either on the internet or in real life) it is best to avoid making these errors since doing so hurts your argument and your credibility. If you have any questions or comments about the following list of fallacies, please let me know.
Ad hominem: attacking the maker of an argument rather than the argument itself. For example, “You only watch the films for Orlando Bloom, therefore no one can take you seriously.” This example does not point out any flaws in the arguments that have been made and instead just attacks the opponent’s character.
Note: Not all insults are ad hominems, and not all ad hominems are insults. A statement is only an ad hominem if it attempts to reject an argument based on some characteristic of the arguer. An insult that does not attempt to reject an argument is not an ad hominem. At the same time, a statement that not have any explicit insults can still be fallacious.
Ad populum: appealing to the sense of “the people”, often invoking emotion, to attack an argument. For example, “We as LotR fans need to be grateful for the amazing films we have and love!” or “Most people think that the films do the books justice, therefore they must.” The first example makes an emotional appeal to the reader, as a member of a group, to think a certain way. The second example suggests that since a lot of people think a certain way, they must be right (i.e., “this many people can’t be wrong!”). However, neither example actually shows any problems with the opponent’s argument.
Appeal to authority: mentioning the name and/or ideas of someone famous or important in support of one’s argument. For example, “Tom Shippey, a noted Tolkien scholar, thinks that the films are faithful to Tolkien so that should be good enough for us.” There is a fine line between committing this fallacy and simply referencing a source, but in general it is fallacious when the authority in question is not an authority in the relevant field or is likely to be biased. Additionally, even valid authorities can be wrong at times, so rebuttals are possible in some cases.
Circular reasoning: using your conclusion as a premise to your argument. For example, “The films are faithful adaptations of the book because they stuck so close to the book.” This argument would work if it included examples of how the films stuck closely to the book, but as it is the premise and conclusion are just two different ways of saying the same thing.
False dilemma: trying to oversimplify a situation so that it appears there are only two possible choices. For example, “PJ could have either stuck exactly to the book or made the films the way he did.” This fallacy completely ignores the middle ground between the two extremes of being more faithful to the book than PJ was or trying to make a carbon-copy of the original text.
Golden mean: assuming that the middle ground between two strongly-held positions must be the correct position. For example, “Both purists and revisionists feel very strongly about PJ’s films, but the truth of the matter must lie somewhere in between.” It is possible that the truth of any given matter might be between two strongly-held positions, but this is not always the case. The mere fact that a given position is a moderate one is not enough to make it correct.
Style over substance: focusing on the manner in which an argument was made rather than the argument itself. For example, “Your messages are very insulting, therefore your points are invalid.” Notice how the example does not actually address any of the points but merely criticizes the opponent’s etiquette, which does not actually have any bearing on the validity of the points.
Red herring: introducing an irrelevant point into the middle of a discussion that distracts from the main topic. For example, “Sure, PJ changed a lot, but he made really good movies!” The red herring claim might be valid, but it is merely a way of avoiding the opponent’s argument rather than addressing it.
Slippery slope: coming to a conclusion based on the premise that if one thing occurs it will be the first step towards an inevitable and negative result. For example, “A filmmaker shouldn’t cut or change anything, because if he does he’ll become comfortable with changes and make even more, and by the time he’s done the film won’t look anything like the book.” This fallacy claims that a reasonable proposition (making some cuts and changes) will inevitably lead to an unreasonable one (making films that look nothing like the original book), even though they are two very different concepts and it doesn’t logically follow that the former must lead to the latter.
Straw man: attacking a distorted and weaker version of your opponent’s argument. For example, “PJ could never have made a film that was 100% percent faithful to the book. The only way he could have was if the films were 10 hours each, and that’s just not a possibility in the movie industry.” Unless of course this is used against someone who actually suggested that every last part of the book should be included in the film (a very small minority of people, if they exist at all), this is attacking a claim that was never made. By addressing the fake argument the maker of this fallacy is ignoring the real argument and the real opponent.
Hasty generalization: a conclusion based on a sample too small to be an accurate representation of the larger pool of samples. For example, “It’s good that PJ cut out a lot of long descriptive passages since those wouldn’t work on film, therefore it’s good that he cut out the Scouring of the Shire.” In some cases it is good to cut portions of the book that won’t work on film, but that doesn’t automatically mean that it’s good to cut other portions as well.
Tautologies: more of a rhetorical technique than a fallacy; tautologies are repetitions of facts that, while true, don’t matter. For example, “books and movies can never be exactly the same.” This is true, but it doesn’t mean that books and movies can’t be more similar than some would allow them to be. In other words, it is irrelevant to almost all purist/revisionist debates.