Bare assertion fallacy

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The bare assertion fallacy is a fallacy in formal logic where a premise in an argument is assumed to be true merely because it says that it is true.

One form of the fallacy may be summarized as follows:

• Fact 1: X claims statement A.
• Fact 2: X claims that X is not lying.
• Conclusion: Therefore, A is true.

Put into practice, this fallacy would read:

• Fact 1: A website says that pigs can fly.
• Fact 2: The same website says that it is true.
• Conclusion: Therefore, pigs can fly.

[edit] See also

• Opaque context
• Transitivity of identity

v • d • e Formal fallacies Argument from fallacy • Fallacy of modal logic • Masked man fallacy • Appeal to probability • Bare assertion fallacy Fallacy of propositional logic: Affirming a disjunct • Affirming the consequent • False dilemma • Denying the antecedent Fallacy of quantificational logic: Existential fallacy • Illicit Conversion • Proof by example • Quantifier shift Syllogistic fallacy: Affirmative conclusion from a negative premise • Exclusive premises • Necessity • Four-term Fallacy • Illicit major • Illicit minor • Undistributed middle Other types of fallacy

[edit] References

• fallacyfiles.org
• Galileo'sRebuttal.html