  Quine and Dummett propose that the logical constants of a language are its grammatical particles—the expressions by means of which complex sentences are built up, step by step, from atomic ones—while non-logical expressions are the simple expressions of which atomic sentences are composed (see Quine 1980, Quine 1986, Dummett 1981, 21–2, and for discussion, Føllesdal 1980 and Harman 1984). On this conception, “[l]ogic studies the truth conditions that hinge solely on grammatical constructions” (Quine 1980,  17).[4] This criterion yields appropriate results when applied to the language of first-order logic (FOL) and other standard logical languages. In FOL (without identity), all singular terms and predicates are paradigm nonlogical constants, and all operators and connectives are paradigm logical  constants.[5]