Paseau, A. C. & Griffiths, Owen: FORMAL VALIDITY: MODEL-THEORETIC AND PROOF-THEORETIC CONCEPTIONS

In Oxford Handbook of Philosophy of Logic. Oxford, UK: Oxford University Press. forthcomingThe usual approach to validity holds that an argument is valid in virtue of its form. This idea has been developed along two main lines: model-theoretic and proof-theoretic. Both frameworks presuppose a distinction between logical and non-logical vocabulary. This chapter introduces these two conceptions of validity and discusses their respective approaches to the demarcation question. We review two version