Genetic fallacy

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A genetic fallacy is a logical fallacy that occurs when a claim is accepted or rejected based on the source of the evidence, rather than on the quality or applicability of the evidence. It is also a line of reasoning in which a perceived defect in the origin of a claim or thing is taken to be evidence that discredits the claim or thing itself. The fallacy is committed when an idea is either accepted or rejected because of its source, rather than its merit.

The genetic fallacy is a logical fallacy but is frequently not a Bayesian one: some sources are so consistently full of it that they reasonably constitute a refutation for all practical purposes.


[edit] Form

Most common:

P1: X said Y is true.
P2: X is a bad source.
C1: Y is not necessarily true.

Less common:

P1: X said Y is true.
P2: X is a bad source.
C1: Y is false.

"Second-option bias" form:

P1: X said Y is true.
P2: X is a bad source.
C1: Anti-Y is true.

[edit] Subtypes

[edit] Examples

[edit] Socrates

  • Socrates says that he is mortal.
  • Socrates is a pagan - only Christians are trustworthy.
  • Therefore Socrates is immortal.

[edit] Hitler

  • "The current Chancellor of Germany was in the Hitler Youth at age 13. With that sort of background, his so called 'reform' plan must be a fascist program."
  • "I was brought up to believe in a god, my parents told me a god exists, and my parents would never lie to me, so this god must exist."
  • "Sure, the media claims that Senator Wales was reading pornography. But we all know about the media's credibility, don't we."

[edit] External links

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