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Fitch Proofs

Name Description Depth
Negation Introduction {p} ⊢ ~~p 0
Negation Elimination {~~p} ⊢ p 0
And Introduction {p, q} p&q 0
And Elimination {p&q} {p, q} 0
Or Introduction {p} {p|q, q|p} 0
Or Elimination {p|q, p=>r, q=>r} r 0
Implication Elimination {p=>q, p} q 0
Biconditional Introduction {p=>q, q=>p} p<=>q 0
Biconditional Elimination {p<=>q} {p=>q, q=>p} 0
Implication Creation {p} q=>p 1
Implication Distribution {p=>(q=>r)} (p=>q)=>(p=r) 1
Implication Reversal {~q=>~p} p=>q 1
Inconsistency {p, ~p} ⊢ q 1
Conditional Deduction {p=>(q=>r), p=>q} ⊢ p=>r 1
Transitivity {p=>q, q=>r} ⊢ p=>r 1
Condition Introduction {q=>r} ⊢ (p=>q)=>(p=>r) 1
Conclusion Introduction {p=>q} ⊢ (q=>r)=>(p=>r) 1
Condition Reversal {p=>(q=>r)} ⊢ q=>(p=>r) 1
Modus Tollens {p=>q, ~q} ⊢ ~p 1
Implication Reduction {p=>~p} ⊢ ~p 1
Contradiction Realization {p=>q, p=>~q} ⊢ ~p 1
 
Universal Conjunction {AX:(p(X)&q(X))} ⊢ AX:p(X)&AX:q(X) 1
Universal Implication {AX:(p(X)=>q(X))} ⊢ AX:p(X)=>AX:q(X) 1
Universal Reversal {AX:AY:p(X,Y)} ⊢ AY:AX:p(X,Y) 1
Existential Universal {EY:AX:p(X,Y)} ⊢ AX:EY:p(X,Y) 1