Variable Assignment in Formal Logic
A variable assignment, sometimes called a variable assignment function, is a crucial…
Upward Löwenheim–Skolem Theorem
The upward Löwenheim–Skolem theorem states that if a first-order theory has an…
Substitution Instance in Logic
A substitution instance is the result of replacing variables in a well-formed…
Skolem Paradox
The Skolem paradox highlights a contradiction between intuition and the Skolem-Lowenheim theorem.…
Satisfaction in Model Theory
Satisfaction in model theory describes the relationship between a structure and a…
Putnam’s Model-Theoretic Argument
Hilary Putnam's argument challenges how we understand reference and truth. It suggests…
Objectual Quantifiers in Formal Logic
Objectual quantifiers are a type of quantifier in formal logic that specifically…
Non-Standard Models in Logic and Mathematics
A non-standard model adheres to a theory's axioms but possesses unintended properties.…