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Philosophy question about logic- methods of deduction?

This problem needs to be expanded using elementary valid argument forms.

1. If not Z then R

2. If (not Z and R) then T

Therefor if not Z then T

Can anyone help? I'm studying for a quiz and can't quite figure this out. I need the name of each rule of inference used. Thanks in advance guys.

Update:

Thank you Anisha, exactly what I was looking for!

2 Answers

Relevance
  • 1 decade ago
    Favorite Answer

    Hi

    Here are a couple of deductions:

    1. ~Z > R Premise

    2. (~Z & R) > T Premise

    3. ~Z > (~Z & R) 1 Absorption

    4. ~Z > T 3,2 Hypothetical Syllogism

    Using a different system:

    (1) 1. ~Z > R Premise

    (2) 2. (~Z & R) > T Premise

    (3) 3. ~Z Assumption

    (1,3) 4. R 1,3 MP

    (1,3) 5. ~Z & R 3,4 &I

    (1,2,3) 6. T 2,5 MP

    (1,2) 7. ~Z > T 3,6 CP

  • ?
    Lv 5
    1 decade ago

    if not yes then no

    if (not yes and no) then maby

    therefor if not yes then maby

    the flaw is here that it could also be no instead of maby

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