Questions about Mathematical Logics
49385
Proving $\forall x (A\to B) \to(A \to \forall x B):x\notin \mbox{free}(A)$ in a Hilbert system where it is not an axiom
137921
Reflexivity, Transitivity, Symmertry of the square of an relation
32244
Propositional Logic - Deduction
141952
Is there a decision procedure for intuitionistic propositional logic?
87928
Proof of logical equivalence of biconditional and other proposition
148790
Basic question about proofs with the goal $\exists x P(x)$
48368
Prove using Natural Deduction in predicate logic $(\forall x\ P(x))\to Q ⊢ \exists x (P(x)\to Q)$
56191
How to demystify the axioms of propositional logic?
121994
What is the philosophical ground for distinguishing logic and mathematics?
21035
Clarifying on how if p,q is logically equivalent to p only if q
48606
Help with a Predicate Logic homework proof
29110
Propositional Intuitionistic Logic Question
73253
Question About equal signs in Theorems
104771
Dedekind's cut and axioms
153510
Questions about the existence of a function
22193
Why, logically, is proof by contradiction valid?
109159
What's the intuition behind $(\exists y)(\mathscr{C}(y)\supset\mathscr{D})\supset((\forall x)\mathscr{C}(x)\supset\mathscr{D})$