I’ve noticed a tendency for the charge of committing the “No True Scotsman” fallacy to be leveled at anyone who favours more restrictive definitions of something than the person leveling the charge favours. This is a misunderstanding of how the “No True Scotsman” fallacy works. Just saying something of the form “No true Scotsman would do X” is not by itself a commission of the “No True Scotsman” fallacy – though the fallacy does involve making a statement of that form. A fallacy has to be an error in inference from one statement to another; a single statement on its ownsome, involving no inference, can’t be a fallacy.
The “No True Scotsman” fallacy arises when someone uses a restrictive version of a definition in order to rebut a counterexample to a claim that was made using a less restrictive definition. So, for example:
1. SMITH: “Democracies never go to war against other democracies.”
2. JONES: “What about the war between Israel and Lebanon? They were both democracies.”
3. SMITH: “No country that commits that kind of aggression counts as a genuine democracy.”
What makes Smith guilty of the “No True Scotsman” fallacy here is not that she employs an idiosyncratically restrictive definition of “democracy” in (3). Employing an idiosyncratically restrictive definition is not by itself a fallacy, since it’s not by itself an argument. If an argument is offered for the idiosyncratically restrictive definition, that argument may of course be fallacious – or it may not. We can’t know until we look at the argument. (Merely using a term more restrictively than in ordinary usage is no proof that the more restrictive usage is wrong; sometimes ordinary usage by itself contains commitments to a more restrictive usage. For example, I think that’s true of the Socrates-Stoic-Cicero-Augustine-Aquinas-Blackstone-Spooner-Lane-MLK Jr. position that an unjust law is no true law.)
Rather, what convicts Smith of the “No True Scotsman” fallacy is the fact that she treats her claim in (3), using “democracy” restrictively, as if it supported her claim in (1), where “democracy” was clearly being used non-restrictively. In other words, the “No True Scotsman” fallacy is an instance of the fallacy of equivocation. (Example of equivocation: “A bank is a safe place to deposit your paycheck; the edge of a river is a bank; therefore the edge of a river is a safe place to deposit your paycheck.” The plausibility of the premises depends on taking them to be using the term “bank” differently; the validity of the inference depends on taking them to be using the term “bank” in the same way.)
If Smith were, clearly and non-obfuscatingly, willing to reject (1) in the non-restrictive sense, and endorse it only in the restrictive sense, then although she might have an implausible definition of “democracy” – and a more vacuous opening claim than initially appeared – she would be innocent of the “No True Scotsman” fallacy.
