Logical Fallacies

• Slippery Slope
  • This is a conclusion based on the premise that if A happens, then eventually through a series of small steps, through B, C,…, X, Y, Z will happen, too, basically equating A and Z.
  • If A, then B, then C, … then ultimately Z!
• Hasty Generalization
  • a fallacy in which a speaker jumps to a general conclusion on the basis of insufficient evidence
  • Sample S is taken from population P. Sample S is a very small part of population P. Conclusion C is drawn from sample S and applied to population P.
• post hoc ergo propter hoc
  • Latin for "after which therefore because of which," meaning that it is incorrect to always claim that something is a cause just because it happened earlier. (correlation does not imply causation):
  • A happened, then B happened. \n A must have caused B.
• Genetic Fallacy
  • Condemning an argument because of where it began, how it began, or who began it.
  • I drank bottled water and now I am sick, so the water must have made me sick.
• Circular Argument
  • This restates the argument rather than actually proving it:
  • X is true because of Y. \n Y is true because of X.
• false dichotomy(either/or)
  • This is a conclusion that oversimplifies the argument by reducing it to only two sides or choices:
  • Either X or Y is true. \n Either X, Y, or Z is true.
• ad hominem
  • a fallacy that attacks the person rather than dealing with the real issue in dispute

    ad populum

    bandwagon appeal; this fallacy occurs when evidence boils down to "everybody's doing it, so it must be a good thing to do." * A lot of people believe X. \n Therefore, X must be true.

• Red Herring
  • A fallacy that introduces an irrelevant issue to divert attention from the subject under discussion
  • Argument A is presented by person 1. Person 2 introduces argument B. Argument A is abandoned.
• Strawman
  • Misrepresenting someone's argument to make it easier to attack

    false equivalence

    a logical fallacy in which two opposing arguments appear to be logically equivalent when in fact they are not: * Person 1 makes claim Y. Person 2 restates person 1’s claim (in a distorted way). Person 2 attacks the distorted version of the claim. Therefore, claim Y is false.

• non sequitur
  • something that does not logically follow:
  • Claim A is made. \n Evidence is presented for claim A. \n Therefore, claim C is true.
• Tu Quoque
  • Dismissing someone's viewpoint on an issue because he himself is inconsistent in that very thing.
  • Person 1 is claiming that Y is true, but person 1 is acting as if Y is not true.

      Therefore, Y must not be true.