 Fitch’s metalogic  From the late 1930s, Frederic Fitch worked on a logic that he called basic logic. The label is motivated by his aim to provide a framework in which any logic could be formalized. Fitch’s approach is utterly syntactic (much like Schönfinkel’s), and “formalization” is to be understood as encoding a formally described system in another—not unlike the arithmetization of the syntax in Gödel’s incompleteness theorem.