>[!abstract] >No true Scotsman or appeal to purity is an informal fallacy in which one modifies a prior claim in response to a counterexample by asserting the counterexample is excluded by definition. Rather than admitting error or providing evidence to disprove the counterexample, the original claim is changed by using a non-substantive modifier such as "true", "pure", "genuine", "authentic", "real", or other similar terms (Wikipedia, 2025). >[!related] >- **North** (upstream): — >- **West** (similar): [[Nirvana fallacy]] >- **East** (different): — >- **South** (downstream): —