[Revised entry by Tero Tulenheimo on September 15, 2022.
Changes to: Main text, Bibliography, notes.html, supplement.html]
Independence friendly logic (IF logic, IF first-order logic) is an extension of first-order logic. In it, more quantifier dependencies and independencies can be expressed than in first-order logic. Its quantifiers range over individuals only; semantically IF first-order logic, however, has the same expressive power as existential second-order logic. IF logic lacks certain metaproperties that first-order logic has (axiomatizability, Tarski-type semantics). On the other hand, IF logic admits a self-applied truth-predicate -…
Originally appeared on Stanford Encyclopedia of Philosophy Read More