How to Derive ((A>B)>A)>A Using Sentential Logic?

Thread starter Cornelius
Start date Nov 6, 2007
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Cornelius

Thread starter
Nov 6, 2007

1. How do you prove, using SD, that ((A>B)>A)>A?

3. I tried to first assume (A>B)>A. Then I made a sub-derivation, assuming ~A. In this sub-derivation, I need to derive a contradiction. How?

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cristo

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Science Advisor

Nov 7, 2007

What does your symbol ">" mean?

How to Derive ((A>B)>A)>A Using Sentential Logic?

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