 Aristotle, General Topics: logic |  Bolzano, Bernard |  Carnap, Rudolf |  Frege, Gottlob: theorem and foundations for arithmetic |  logic, normative status of |  logic: algebraic propositional |  logic: classical |  logic: inductive |  logic: intuitionistic |  logic: non-monotonic |  logic: substructural |  logical constants |  logical form |  logical pluralism |  logical truth |  model theory |  proof theory |  Russell, Bertrand |  schema |  semantics: proof-theoretic 