New posts in predicate-logic

Deduction Theorem: only works with closed formulas?

logic predicate-logic first-order-logic

Online tools for checking validity of classical, intuitionistic, ... logic formulas?

propositional-calculus predicate-logic first-order-logic online-resources constructive-mathematics

Restrictions on the use of universal generalization

logic predicate-logic first-order-logic natural-deduction

Math logic versus Semantic Web use of predicate

predicate-logic

What is the logical flaw in this reasoning? Abusing $T \equiv T \vee F$.

logic first-order-logic predicate-logic

How to write “there exists an infinite number of”?

notation predicate-logic

What is the justsification for this restriction on UG?

logic predicate-logic

Simplest axiom that entails the existence of an infinite set

set-theory first-order-logic predicate-logic infinity axioms

Quantifiers, predicates, logical equivalence

discrete-mathematics logic predicate-logic quantifiers

What exactly is a contradiction and how does it differ from falsity?

logic propositional-calculus first-order-logic predicate-logic

How to prove that Gödel's Incompleteness Theorems apply to ZFC?

logic set-theory predicate-logic first-order-logic incompleteness

What will be the negation of this statement:

logic predicate-logic first-order-logic quantifiers

A question on the diagonal lemma

logic first-order-logic predicate-logic fixed-point-theorems

Logically Necessary but NOT Tautologically necessary? Help

logic propositional-calculus first-order-logic predicate-logic

Simple Fitch Proof without using DeMorgan's Law

logic solution-verification proof-explanation first-order-logic predicate-logic

⊢∃𝑥(𝜙⟹∀𝑥𝜙) using Hilbert-style proof [duplicate]

logic first-order-logic predicate-logic formal-proofs

Classes, sets and Russell's paradox

logic propositional-calculus predicate-logic

In classical predicate logics, why is it usually assumed that at least one object exists?

logic predicate-logic model-theory philosophy

Disproving the statement $\alpha\rightarrow\beta\models\forall x.\alpha\rightarrow\forall x.\beta$

logic predicate-logic

Need help with Fitch proof.

logic propositional-calculus predicate-logic