I am trying, given ((p ⇒ q) ⇒ r),, to use the Fitch System in order to prove
((p ⇒ q) ⇒ (p ⇒ r)).
Any ideas on how I should proceed?
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Phani
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These steps will help you in this proof :
1 (p => q) => r Premise
2 p => q Assumption
3 p Assumption
4 q Implication Elimination: 2,3
5 r Implication Elimination: 1,2
6 p => r Implication Introduction: 5
7 (p => q) => (p => r) Implication Introduction: 6

Mojo Jojo
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