The No True Scotsman Fallacy Is An Appeal To Purity

The No True Scotsman fallacy occurs when one side of an argument makes a universal claim, is presented with an exception to refute that claim, then dismisses that counterexample as not being "pure" enough. The example this fallacy is named for goes like this: one Scotsman declares that no Scotsman puts sugar on his porridge. Another points out that he's a Scotsman, and he puts sugar on his porridge. To that, the first replies that no true Scotsman puts sugar on his porridge. The problem here is that whether or not those who put sugar on their porridge are "true" Scotsmen is a subjective claim, or just a statement of opinion. Opinions are weak evidence for an argument. The porridge example is a trivial one, but this fallacy shows up in all sorts of sinister ways. Often, it's used to exclude people from a group. How often have you heard that someone isn't a real man, a real American, or a true Christian for a "distasteful" quality they have or action they've taken? It's also used to condemn or promote an entire group of things: all real video games make children violent, for example, or all true citizens vote their conscience. To avoid this fallacy, focus on the individual pieces of evidence that back up your argument rather than picking apart your opponent's counterexamples. To help you make your case, check out the videos on other logical fallacies below.


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The No True Scotsman Fallacy

No true fan of fallacies would skip this video.

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Key Facts In This Video

  1. The "No true Scotsman" fallacy calls the legitimacy or purity of something into question as a way to refute an argument. 00:18

  2. British philosopher Anthony Flew is credited with the first mention of the "No true Scotsman" fallacy. 00:52

  3. To avoid the "No true Scotsman" fallacy, debaters can discuss the perceived definition and fluidity of a certain category. 01:42

The Gambler's Fallacy

If your coin toss lands on heads 20 times in a row, what are the chances the next one will be tails?

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Five Logical Fallacies

Hear about five of the most common fallacies you'll come across.