query: How can I prove $B ∨ ¬B$ without using assumption and contradiction?
positive_passages.docid: 151561
positive_passages.text: Proving 'Law of Excluded Middle' in Fitch system
negative_passages.docid: 31299
negative_passages.text: Using the Fitch system, how do I prove $((p \implies q) \implies p)\implies p$?
negative_passages.docid: 80255
negative_passages.text: How to prove that $|a-b|<\epsilon$ implies $|b|-\epsilon<|a|<|b|+\epsilon$?
negative_passages.docid: 17073
negative_passages.text: Using proof by contradiction vs proof of the contrapositive
negative_passages.docid: 22193
negative_passages.text: Why, logically, is proof by contradiction valid?
negative_passages.docid: 91861
negative_passages.text: Propositional Logic: p → q, ¬p → r, ¬q → ¬r ⊢ q
negative_passages.docid: 84562
negative_passages.text: Proof using only field axioms
negative_passages.docid: 100421
negative_passages.text: How to write this boolean expression using only NOR gates?
negative_passages.docid: 89535
negative_passages.text: fake proof of $\forall a. \forall b. a = b \to 1 = 0$
negative_passages.docid: 13012
negative_passages.text: Why can a = b imply 2 = 1?
negative_passages.docid: 87928
negative_passages.text: Proof of logical equivalence of biconditional and other proposition
negative_passages.docid: 10598
negative_passages.text: Contrapositive Fitch Proof
negative_passages.docid: 125263
negative_passages.text: How to crack the proof
negative_passages.docid: 113344
negative_passages.text: How do we prove that something is unprovable?
negative_passages.docid: 142762
negative_passages.text: how to prove that (P⊃Q)≡(¬Q⊃¬P) ( P ⊃ Q ) ≡ ( ¬ Q ⊃ ¬ P ) is disallowed in intuitionistic logic?
negative_passages.docid: 6535
negative_passages.text: Proof of for-all / there-exists "negation"?
negative_passages.docid: 136577
negative_passages.text: In formal logic, how is it possible for an argument with a contradictory conclusion to be valid?