Single Idea 11002

[catalogued under 10. Modality / A. Necessity / 2. Nature of Necessity]

Full Idea

C.I.Lewis's S4 system develops a sense of necessity as 'provability' in some fairly informal sense.

Gist of Idea

Equating necessity with informal provability is the S4 conception of necessity

Source

report of C.I. Lewis (works [1935]) by Stephen Read - Thinking About Logic Ch. 4

Book Reference

Read,Stephen: 'Thinking About Logic' [OUP 1995], p.118