Argumentum ad nauseam

A lie repeated a thousand times doesn’t become true!

Source, wikipedia
Also argument ad infinitum or argument from repetition, it is a fallacy which favors a claim by its continuing reiteration, either by one person or many people. The appeal to these arguments implies that one of the parts is encouraging a superfluous discussion in order to evade arguments that can’t be replied to, insisting on matters already discussed, explained or rebated. This fallacy is usually employed by politicians, religious believers and rethoricians, and it is one of the main devices they use to reinforce urban legends by repeating true or false claims until they become established as the beliefs of one individual or a whole society, thus becoming incontestable facts.

It is a well known quote, allegedly by the Nazi Propaganda Minister Joseph Goebbels: “A lie repeated often enough becomes accepted truth”.
Another example, also really common in politics, consists of presenting oneself as a victim, and repeating it more intensely the more fake the claim is, when whoever is maintaining the fallacy is actually attacking the supposed attacker, pleading self defence.

To refute it
To highlight the interests and prejudice that make the affirmation referred to so popular. As well as underlining the facts that prove it to be false, of course.

Whenever the source is not referenced, both definitions and examples have been extracted from a translation of Jaime Wilson based on Stephen’s Guide to the Logical Fallacies. Copyright 1995-1998 Stephen Downes. Brandon, Manitoba, Canada.

These texts have been modified by Miguel A. Lerma and now by us to adapt them -and those taken from Wikipedia- to our format.