On Mates's puzzle

Abstract

I defend a metalinguistic account of Mates's puzzle: sentences where synonymous expressions cannot be substituted salva veritate. If Andrea thinks that attorneys are different from lawyers, and she thinks that Fiona is the former but not the latter, we may hesitate to substitute 'lawyer' for 'attorney' in 'Andrea believes that Fiona is an attorney', even though 'lawyer' and 'attorney' are synonymous. I argue that these sentences report de re beliefs about linguistic expressions, thereby blocking such substitutions, and I offer a compositional derivation of their meaning.