Die vier Wissenschaften der Pythagoreer. Hundert Jahre formale Logik: 247. Sitzung am 1. Dezember 1976 in Düsseldorf

Formal logic presupposes a formal language. A rudimentary formal language was given by G. Boole. A formal language which was sufficient for the purpose of mathematics was constructed by Gottlob Frege in his book " Begriffsschrift, eine der arithmetischen nachgebildete Formel- sprache des reinen Denkens" (1879). Since that time we have an abun- dant spectrum of logics based on formal languages. There are applications mainly in mathematics ("metamathematics"), but also e. g. in philos- ophy, ...