1 THEORIES OF MEANING
The phrase ātheory of meaningā occupies a central place in philosophical logic. Yet that phrase is ambiguous. We need to distinguish:
(1) a (perhaps formalized) theory which, for some particular language L, yields a meaning specification for each well-formed sentence of L; that is, a theory which yields a theorem of the form
s means (in L) that p
for each sentence s of L;
(2) a (discursive) theory which illuminates the concept of meaning; that is, a philosophical account which analyses meaning in terms of other concepts, or at least reveals the location of the concept of meaning with respect to other concepts.
Concerning theories of meaning in the first sense (theories1 of meaning), there are five brief preliminary points to be made. Someone might be concerned that, if a theory1 of meaning for English is a theory which yields such theorems as
āEverest is a mountainā means (in English) that Everest is a mountain
then a theory1 of meaning is something with an air of triviality about it. The first three points are intended to ease that worry, although the third also has a stipulative component.
(1) A theory1 of meaning is a theory about a particular language, the object language (OL), and it is itself cast in a particular language, the metalanguage (ML). But what the theorems of the theory state in the ML about particular OL sentences could as readily be stated in any of a host of languages. What a Frenchman knows when he knows what the English sentence āEverest is a mountainā means is just what an Englishman knows when he knows what that sentence means, although what a Frenchman would write down as part of a theory1 of meaning for English would be a French sentence mentioning that English sentence and so would be different from what an Englishman would write down as part of a theory1 of meaning for English.
(2) A theory1 of meaning for one language cast in a second language is very different from a theory of translation for the first language into the second, even if the language in which the theory of translation is cast is itself the second language. We must contrast:
(i) āKungen vet att Stockholm Ƥr en stor stadā means (in Swedish) that the King knows that Stockholm is a large city;
(ii) āKungen vet att Stockholm Ƥr en stor stadā means (in Swedish) what āThe King knows that Stockholm is a large cityā means (in English).
In (i) a certain English sentence is used in specifying the meaning of a Swedish sentence. In (ii) that same English sentence is mentioned as a sentence which means the same as the Swedish sentence. What obscures the difference is that, since the translation theory is cast in English as well as being a theory of translation into English, anyone who can read the theory probably knows what the mentioned English sentence means, and so can come to know what the Swedish sentence means. But the difference remains. What is stated by (i) is something knowledge of which itself suffices (e.g. in a Frenchman) for knowing what the Swedish sentence means. What is stated by (ii) is something knowledge of which does not itself so suffice (e.g. in a Frenchman). (On this point, see Lewis, 1972, pp. 169ā70, and Evans and McDowell, 1976, pp. vii-xi.)
(3) The meaning specifications provided by a theory1 of meaning for a language might or might not provide conceptual analyses of the meanings of sentences of that language. A theory1 of meaning for Swedish in English might specify the meanings of Swedish sentences containing the present tensed verb āvetā either by using the simple verb āknowsā or by using the phrase āhas a justified true belief. Using the phrase to provide a conceptual analysis provides greater philosophical illumination, but that illumination is a contribution to epistemology rather than to philosophical logic. A meaning specification may be conceptually unilluminating, in this sense, without being trivial or empty. What is stated by a meaning specification which does not provide conceptual analysis, for a Swedish sentence containing āvetā, is something that most people do not know. It is not built into the notion of a theory1 of meaning, as that notion is used here, that the theorems of such a theory should provide conceptual analyses. (We allow, in the terminology of Dummett, 1975, that a theory1 of meaning may be modest rather than full-blooded.)
The fourth and fifth points are of an almost wholly stipulative character. The fourth is related to the topic of Chapter III. The full significance of the fifth will be seen in Chapter VIII.
(4) A theory1 of meaning for a particular language L might have for each sentence of L an axiom specifying that sentenceās meaning. If L had infinitely many sentences then the theory would have infinitely many proper axioms (that is, infinitely many axioms other than those of the background logic of the theory). This would prevent a theorist from listing all the proper axioms, but it need not prevent him from specifying them. There might be an effectively recognizable feature such that the proper axioms are all and only the sentences of the ML which have that feature. In that case the proper axioms could be specified by a proper axiom schema. As we shall see (in Section III.l) there is a project which a theory1 of meaning will not serve well if it simply has an axiom for each sentence of the OL. But it is not built into the notion of a theory1 of meaning, as such, that it should have only finitely many proper axioms.
(5) A theory
1 of meaning for a particular language seems to state contingent facts about that language. It seems to be a merely contingent truth that āDet regnarā means (in Swedish) that it is raining. Here we face a choice. We could regard a language as
a changeable and indeed changing thing. In that case Swedish is a language which has the contingent property that in it, at present, āDet regnarā means that it is raining. But let us instead regard a language as an unchanging and, indeed, unchangeable thing. It is a consequence of this stipulation that the language which is in fact at present spoken in Sweden has the non-contingent property that in it āDet regnarā means that it is raining. A language in which those words did not mean that it is raining would be a different language. But we still have room for a contingent fact. It is a contingent fact that the people of Sweden speak a language in which āDet regnarā means that it is raining. A quite different language could, if things had gone differently, have been spoken in that country./Ignoring for the moment both context dependence and ambiguity we could regard a language as an order pair
where
is a set of sentences and
is a set of meaning specifications, one for each sentence in
. If
< > =
L and
s is a sentence of
for which
specifies.
s means that p
then s is a sentence of L and s means (in L) that p (cf. Lewis, 1975, p. 3).
With the notion of a theory1 of meaning thus clarified we must face a very natural question. How could any contribution be made to philosophical logic by attending to theories1 of meaning for particular languages? For if one seeks to construct theories which provide conceptual analyses then one may contribute to philosophy but not specifically to philosophical logic, while if one seeks to construct theories which do not provide conceptual analyses then one may contribute, at best, to international relations or tourism.
One answer to this question is that a contribution can be made to philosophical logic by stating, quite generally, under what conditions a correct theory1 of meaning for a language L is an adequate theory for the language of a given population G;that is, by stating under what conditions the language L is the actual language of G. (Let us ignore populations with bilingual members.) To state these conditions would be to provide a theory2 of meaning, that is, a philosophical elucidation of the concept of meaning.
2 PROPOSITIONAL ATTITUDES AND ACTUAL LANGUAGES
The thought that elucidation of the concept of linguistic meaning (meaning in a language) must proceed via an account of what it is for members of a population to speak that language is a compelling one. It does not require us to deny that there are languages which no one speaks. It just requires us to deny that the significance of the claim that a certain sentence s means that p in a language L can be appreciated independently of any consideration of what it would be to speak L.
If members of a population G share a language L in which s means that p then those members can use utterances of s to express their belief that p. This claim is very rough, but refining it promises to yield us an account, employing the concepts of the propositional attitudes (belief, desire, intention, and so on), of what it is for L to be the actual language of G. That account will constitute a condition of adequacy upon any theory which purports to be a theory1 of meaning for the language of G. Let us call any such condition of adequacy a propositional attitude constraint (PAC).
To see more clearly why there will be some such
PAC which a theory must meet with respect to a population, if that theory is to be an adequate theory
1 of meaning for the language of that population (equivalently: if the language for which that theory is a correct theory
1 of meaning is to be the actual language of that population) imagine that a language
L =
is spoken in a population
G. Then the meaning specifications in
can contribute towards our interpretation of the utterances, by members of G, of (indicative) sentences in
and of sentences (in other moods) closely related to sentences in
; that is, towards our redescription of those utterances as linguistic acts of certain
kinds (assertions, commands, questions, and so on) and with certain
content...