Single Idea 13136

[catalogued under 4. Formal Logic / D. Modal Logic ML / 2. Tools of Modal Logic / a. Symbols of ML]

Full Idea

A 'prefix' is a finite sequence of positive integers. A 'prefixed formula' is an expression of the form σ X, where σ is a prefix and X is a formula. A prefix names a possible world, and σ.n names a world accessible from that one.

Gist of Idea

The prefix σ names a possible world, and σ.n names a world accessible from that one

Source

M Fitting/R Mendelsohn (First-Order Modal Logic [1998], 2.2)

Book Reference

Fitting,M/Mendelsohn,R: 'First-Order Modal Logic' [Synthese 1998], p.48