© 2011-2019 by Zack Smith. All rights reserved.
No True Scotsman
An arguer who wishes to maintain the proposition P will simply
modify the definition of its subject
Scotsmen) to exclude the validity of the counterexample
and maintain the
goodness of the subject.
We dislike the idea that a Republican might support atheistic ideas. Therefore no true Republican is an atheist.
One needs only notice the redefinition and point out that, every time the arbitrary characteristic is at risk of being shown to be invalid, the arguer revises the subject definition rather than accept new evidence that requires a more diverse definition.