P. M. S. Hacker on Rudolf Carnap and H. P. Grice

"Carnap, unsurprisingly, was incredulous."

"Carnap's account of analyticity, he remonstrates, is intended as an *explication* of the philosophical concept of analyticity as applied to an ordinary language such as English, which is indeed imprecise, since expressions in ordinary language do not have sharply defined meanings."

"Quine argues that he did not know whether ‘Everything green is extended’ is analytic or not, and he attributed his uncertainty to the unclarity of the term ‘analytic’ (TDE 32)."

"Carnap objects that the unclarity is due *not* to the term ‘analytic’, but to the fact that it is unclear in an ordinary language such as English whether the term ‘green’ is applicable to a single spatio-temporal point, where a point is construed as lacking extension, since ordinary language does not talk of points thus construed."

"Grice and Strawson strengthen Carnap’s point in noting that the same uncertainty attaches to the question of whether it is true that everything green is extended - and Quine could hardly complain that the term ‘true’ is irremediably unclear."

"In a constructed language, one lays down meaning postulates in order to ensure clarity."

"Hence, if it is a meaning postulate that ‘G’ (‘green’) is inapplicable to spatio-temporal points, ‘(x) (Ux z> ~ Gx)’ is analytic in L, and so is ‘(x) (Gx z> Ex)’ (where ‘U’ signifies ‘unextended’ and ‘E’ ‘extended’).

"Analytic in L," Carnap argues, signifies sentences whose truth depends on their meanings alone, and is thus independent of the contingency of facts, or ‘true in virtue of meanings’.

"Of course, it does not follow that such statements cannot be revoked."

"The same sentence can be analytic in one system and synthetic in another."

"An analytic truth is unrevisable only in the sense that it remains analytically true as long as the language rules are not changed."

"Carnap might have added that it is anything but obvious what it would be to revise one’s belief that every bachelor is unmarried, without changing the use (or meaning) of the expression."

"The attribution of truth to synthetic sentences may be changed in the light of experience, even though the logical structure of the language does not change."

"The analytic/synthetic distinction can be drawn always and only with respect to a language system, i.e. a language organised according to explicitly formulated rules, not with respect to a historically given natural language [such as English]’
-- Carnap, ‘Quine on Analyticity’, in "Dear Carnap, Dear Van."