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Valid Argument

Edited by Normal_Anomaly, Vladimir_Nesov last updated 22nd Jan 2011

An argument is valid when it contains no logical fallacies. Such arguments are not necessarily sound, because the premises may be false. For instance, the following syllogism is valid but has a false conclusion:

  • All animals are dogs. (False premise/All A are B.)
  • All dogs are terriers. (False premise/All B are C.)
  • Thereforse, all animals are terriers. (False conclusion: not all animals are terriers. Valid logic: If all A are B, and all B are C, then all A are C.)

Blog posts

  • The Parable of Hemlock (tangentially related)

See also

  • Sound argument
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