Card Set Information

2011-11-29 10:36:22

Basic Logical Concepts
Show Answers:

  1. Logic:
    The study of the methods and principles used to distinguish correct from incorrect reasoning
  2. Argument:
    from logitians point of view, is a series of propositions, some of which are premises, others of which are conclusions
  3. Logic is not:
    • 1. Science of thought (psychology)
    • 2. Science of reasoning(cog. psy.)
    • 3. The art of persuasion "rhetoric"
  4. We are interested in:
    causes us to think the way we do
  5. Propositions, while expressed by sentences:
    they are not equivalent to sentences
  6. Questions and explanations :
    are sentences but not propositions
  7. Commands:
    • are sentences but not propositions
    • These Can be turned into propositions though
  8. Example of command:
    Do your homework -> You should doyour homework if you want topass the class.
  9. Temporal relations;
    • prop. that appears to be butisnt
    • one indicating a before and after
    • ex. since the nig has been president, the economy has gone to hell.
  10. Arguments do not =
  11. Conditional statement(hypothetical) while not;
    • an argument it can still be part of one
    • compound prop.
    • it is false only when the antecedent is true and the consequent is false
  12. Proposition:
    An assertion that something is (or isnt) the case; they are either true or false
  13. Inductive:
    • invalid
    • if premises are true doesnt mean conclusion is
    • premises only make the conc. LIKELY to true but not absolutely
    • *prediction of future is always inductive
  14. Deductive
    • validq
    • if premises are true then the con. has to be true
  15. Four kinds of inductive arguments
    • 1. predictions about future
    • 2. argument from analogy
    • 3. inductive generalization
    • 4. causal inferences
  16. Argument from analogy
    the premises indicate how a number of objects are similar and inferences drawn, given that it is reasonable to say they are similar in ways we dont know about and ways we do
  17. Example of arg. from analogy
    • Tom and Hank and Dick all own BMW Z3 2009 built in Greer
    • Tom and Dick's cars get 37 miles togallon (we dont know how much Hanks gets but we assmue it is the same)
  18. Inductive generalization
    • The premises give us information about a sample (subset) of some group. The conclusion is that the findinngs of the sample are true for the whole.
    • We generalize
  19. Causal inference
    • Has premises that provide that something has happened, the con. provides some causation of the event.
    • Causes and effects
  20. Example of Causal inference
    I forgot to put the ice cream up before i went to bed (we infer a certain effect) infer that itmelted. - Maybe someone else put it away...there are alternative accounts forother reasons
  21. If i intend that my premises are saying the truth for the conclusion, then it is
  22. Deductive can only either be;
    • valid
    • invalid
  23. Refutation by counter example
    • 1. If A, then B
    • 2. Not A
    • 3. Not B

    • If obama were a rockstar he'd be famous
    • Obama isnt a fockstar
    • Obama isnt famous
  24. Classical logic
    • traditional techniques
    • based on aristotles works for the analyses of deductive arguments
  25. Fallacy
    a type of argument that may seem to be correct but contains a mistake in reasoning
  26. Fallacies of Relevance
    fallacies in which the premises are irrelecent to the conclusion
  27. 5 types of fallacies of relevance
    • 1. the appeal to emotion
    • 2. the appealto pity
    • 3. the appealto force
    • 4. argument against the person
    • 5. irrelevant conclusion
  28. Appeal to emotion
    • Fallacy in which the argument relies on emotion rather than reason.
    • ad populum
    • boarders on brainwashing
    • type of propaganda...bandwagon effect
  29. Appeal to pity
    fallacy in which the arg. relies on gerosity, altruism, or mercy, rather than reason
  30. Appeal to force
    fallacy in which the arg relies on the threat of force; threat may be veiled.
  31. Argument ad hominem
    • fallacy in which the erg. relies on an attack against the person taking a position
    • can be abusive or circumstantial
  32. Irrelevent conclusion
    type of fallacy in which the premises support a different con. than the one that is proposed
  33. Fallacies of presumption
    fallacies in which the con. depends on a tacit assumption that is dubious, unwarranted, or false
  34. Types of presumption fallacies
    • 1. fallacy of accident
    • 2. complex question
    • 3. begging the question
  35. Fallacy of accident
    fallacy in which a generalization is wrongly applied to a particular case
  36. Complex question
    fallacy in which a question is asked in a way that presupposes the truth of some proposition buried within the question
  37. Begging the question
    • fallacy in which the con. is stated or assumed within one of the premises
    • also known as circular argument
  38. Fallacies of ambiguity
    fallacies causes by a shift or confusion of meanings within an argument
  39. types of ambiguity fallacies
    • 1. fallacy of equivocation
    • 2. fallacy of amphiboly
    • 3. fallacy of accent
    • 4. fallacy of composition
    • 5. fallacy of division
  40. Fallacy of equivocation
    fallacy in which 2 or more meanings of a word or phrase are used in different parts of an argument
  41. Fallacy of amphiboly
    • fallacy in which a loose or awkward combination of words can be interpreted in more than 1 way.
    • The premise is based on 1 interpretation while the con. relies on a different interpretation
  42. Fallacy of accent
    fallacy in which a phrase is used to convey 2different meanings within an arg. and the difference is based on changes in emphasis given to words within a phrase
  43. Fallacy of composition
    fallacy in which an inference is mistakenly drawn from the attributes of the parts of a whole, to the attributes of the whole
  44. Fallacy of division
    fallacy in which a mistaken inference is drawn from the attributes of a whole to the attributes of the parts of the whole