Single Idea 10897

[catalogued under 5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic]

Full Idea

A formula of a first-order language is a 'sentence' just in case it has no free variables.

Gist of Idea

A first-order 'sentence' is a formula with no free variables

Source

José L. Zalabardo (Introduction to the Theory of Logic [2000], §3.2)

Book Reference

Zalabardo,José L.: 'Introduction to the Theory of Logic' [Westview 2000], p.89