logic_3_4

  1. Fallacies of presumption
    • premises presume some crucial piece of information
    • a presumption exists-- embedded in the premises-- that the conclusion is true or
    • the conclusion is not assumed true, but another piece of information is presumed true
  2. Begging the Question
    • most traditional of the fallacies of presumption
    • an arguer uses some type of linguistic trick to conceal the questionable nature of a premise
    • first version is when a premise restates the conclusion -circular reasoning
    • -restating the information in a different form -attempt to conceal
    • second form uses a hidden premise that is problematic in nature
  3. Complex Question
    • not explicitly an argument. However, an implied argument is being made
    • generally designed to trap the person the question is directed at into
    • admitting something he might not otherwise admit to
  4. False Dichotomy
    • falsely limits the listener to two choices
    • failing to account for a legitimate alternative
    • False dichotomy = false disjunction
  5. Suppressed Evidence
    • deliberately ignores evidence that undermines the conclusion of his argument
    • presuming an argument true despite evidence to the contrary
    • must determine if all relevant evidence is presented
  6. Fallacies of Ambiguity
    • premise, conclusion or both are ambiguous in some fashion
    • word, a phrase, or a sentence is subject to different interpretations
  7. Fallacies of Ambiguity -Equivocation
    • definition of an ambiguous word or phrase is changed during the course of an argument
    • : Hitler's talk of a master race was harmless. He was just referring to a sporting event!
    • -term race is being used in two ways, to refer to ethnicity and to refer to a sporting event
  8. Fallacies of Ambiguity -Amphiboly
    • occurs when a statement that has a structural defect is misinterpreted by someone
    • an entire statement being ambiguous

    • Molly told Peggy that she is 9 months pregnant. Peggy must be due any day now.
    • Molly told Peggy that Molly is 9 months pregnant
  9. Fallacies of Grammatical Analogy
    • rguments which are grammatically analogous to-- have a linguistic structure similar to-- legitimate arguments
    • - composition and division
  10. Fallacies of Grammatical Analogy -Composition
    • reasoning that since the parts of an object possess certain characteristics, the object itself will, too.
    • - Every part of this refrigerator weighs less than 10 pounds. Therefore, this refrigerator weighs less than 10 pounds.
  11. Fallacies of Grammatical Analogy - Collective distribution
    Terms can be used either collectively or distributively. When a term is used collectively, it refers to a group as a whole. When a term is used distributively, it refers to the individual members of the group
Author
aprilhudson
ID
9721
Card Set
logic_3_4
Description
Fallacies from 3.4
Updated