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“On Sense and Reference”

قسمت اول: مقدمه

Frege is widely regarded as the father of analytic philosophy. His work has shaped everything which has been written in the philosophy of language in the analytic tradition. I think there are two principal reasons for this. First, his philosophy of language presents a way of accepting what seems most natural and intuitive about the kind of approach to language found in Locke, while decisively rejecting what seems most questionable about it. And, secondly, his work offers the prospect of thoroughly systematic approach to meaning.

Frege shares with Locke these three crucial assumptions:

(L1) The nature of language is defined by its function;

(L2) The function of language is to communicate;

(L3) What language is meant to communicate is thought.

But his clearest disagreement with the Lockean tradition comes in his treatment of these two assumptions:

(L4) Words signify or mean the components of what language is meant to communicate; 

(L5) The components of thoughts are ideas.

Frege accepts some version of (L4) but understands it in a non-Lockean way. Locke had the following conception of how words –or most of them, at least- stand for self-standing Ideas in the mind of the speaker, and these are combined into something sentential by an action of the speaker’s mind. Frege rejects this: sentences are, in some sense, basic, and individual words only make sense in the context of sentences.

The other striking innovation of Frege’s philosophy of language is his use of the materials of formal logic to characterize the meaning of words.

 

قسمت دوم: Psychologism and the Context Principle

Frege:

(F1) It is not true that all words mean or refer to Ideas;

(F2) The meaning of a word is what is known by someone who understands the word.

The Context Principle:

First formulation: Never to ask for the meaning of a word in isolation, but only in the context of a sentence.

Other: It is only in the context of a sentence that words have any meaning.

Last version:

(CP) There is no more to the meaning of a word than its contribution to the meaning of sentences in which it may occur.

Why should we accept (CP)? Frege’s principle reason was that unless we insist on (CP), we’ll be driven to think that words mean Ideas. There’s also another reason for accepting (CP): it gives us at least the beginning of a response to the problem of the unity of the sentence. The response suggested by (CP) is this: we don’t try to explain the unity of a sentence as something generated from independently meaningful parts; instead we take the unity of the sentence as basic.

Frege seems also to have implicitly endorsed a kind of converse principle, which we can call the Principle of Compositionality:

(PC) There is no more to the meaning of a sentence than what is determined by the meaning of words of which it is composed and the way in which they are arranged.

(PC) is the core principle in the study of semantics. Semantics is the systematic explanation of how the meaning of words determines the meaning of sentences composed from them.

Here is the problem. (CP) says that sentences are basic; (PC) says that words are basic. One suggestion (by Davidson) might be this. The sentence is basic in our understanding of the relation between language and what is outside of language. But the word is basic in our understanding of the relation between each sentence and the rest of language.

 

قسمت سوم: فرگه و منطق

Frege’s whole approach to language was shaped by his work on logic. Philosophy of language is shaped by the conception of validity which is implicit in his system:

(V) An argument is valid if and only if it is impossible for all of its premises to be true and its conclusion false.

Frege’s logic is built in two layers. The basic layer of Frege’s logic is sentence logic. This is concerned with arguments which depend on relations between whole sentences. The next layer –known as predicate logic- is concerned with arguments which depend on relations between parts of sentences. At its heart is a view of how sentences divide into parts. At bottom, Frege recognizes two basic kinds of parts of sentences. One kind consists of words or phrases which refer to particular individual objects –these are known as singular terms; Frege called them proper names. The other kind of basic part of sentences is the predicate. A predicate is just the result of removing one or more singular terms from a sentence.

Since Frege’s logical system depends on the simple definition of validity given by (V), we can specify quite simply what matters about the meaning of each of these three kinds of linguistic unit:

For sentences –whether they are true or false;

For singular terms –which objects they refer to;

For predicates –what difference they make to the truth and falsity of sentences, given any particular choice of singular terms in place of variables.

 

قسمت چهارم: reference

Two important words:

Bedeutung: reference

Sinn: sense

The basic of Frege’s mature account of language is his theory of Bedeutung. There are two striking things about this. First, he takes Bedeutung to account for what matters about meaning for the purposes of logic and perhaps for science in general. And, secondly, he understands Bedeutung in a way which the German word makes natural, but would seem odd to us if we took it to be simply equivalent to ‘meaning’. It is natural to translate the word ‘Bedeutung’, as it is used in Frege’s mature philosophy, as reference.

It is natural to say that singular terms refer to objects, and this is what Frege says. The cases of predicates and sentences are harder, though. Frege proposed that predicates should be said to refer to functions of particular kind. These are functions from objects to truth and falsity. Frege called functions of this kind concepts, and predicates concept-words. Frege also claims that sentences have referents too. Clearly what matters about sentences for Frege’s logic is their truth or falsity. Frege, In effect, turned truth and falsity into things and named them the True and the False. The True and the False are the values of the functions referred to by predicates, so they’re known as truth-values. He claims that it is only the truth-values of sentences which remain unchanged if you exchange their component words with other words whose reference is the same, and concludes that sentences refer to their truth-values.

 

قسمت پنجم: sense

Frege’s theory of reference leaves a huge gap between the reference of expressions and what might ordinarily be called their meaning. He used the word ‘Sinn’ to refer to this extra dimension of meaning. The word is translated Sense.

Compare these two:

(1)   (2*2^3)+2=18

(2)   18=18

Equation (1) can give us new knowledge, but equation (2) cannot; (1) is informative, while (2) is not.

In Begriffschrift, his early logical work, Frege had supposed that identity statements were really about the words involved: they said just that the words on the left had the same content as the word on the right. In the famous paper ‘Uber Sinn und Bedeutung’, he now thinks that this won’t do.

Frege proposes that there’s a further aspect of what we would ordinarily call the meaning of words –in addition to their reference. This further aspect he calls Sense. Frege then claims that although ‘(2*2^3) + 2’ and ‘18’ have the same reference, they differ in Sense. Sense contains the mode of presentation of referent.  

Frege thought that all kinds of linguistic expression could have Sense as well as reference. In particular, he thought that sentences as whole had Sense, and he thought that the Sense of sentences were what we ordinarily think of as Thoughts: the Sense expressed by a sentence is the Thought.

 

قسمت ششم: استفاده‌هایی از مفهومِ Sene

As he introduces it, Frege’s notion of Sense is defined in terms of informativeness. A true sentence is informative if you can understand it without thinking that it’s true.

Having introduced the notion of Sense to deal with the problem of informative identity statements, Frege used it in a way that offers solutions to two further problems.

The first is what to do about sentences containing singular terms which don’t refer to any real thing. There are two kinds of case here. The first is that of sentences involving singular terms which are semantically complex (example: ‘the least rapidly converging series’). A different kind of case is that of sentences in fiction:

(5) Odysseus was set ashore at Ithaca while sound asleep.

Frege suggests that the name ‘Odysseus’ has sense, but no reference, and the sentence (5) as a whole expresses a Thought, even though it has no truth-value

The other problem Frege uses the notion of Sense to solve is one that arises in offering a semantics for ordinary languages. Such languages contain devices for reporting speech indirectly (‘Galileo said that …’), and for describing the thoughts and feelings of people (‘Amy believe that …’). Let us call all of these forms of word devices for introducing indirect contexts, in which sentences are used to report sayings, thoughts, and feelings indirectly, as opposed to by means of direct quotation.

Consider the case of Carol, a classicist. The following sentence involving an indirect context is true:

(6) Carol thinks that the evening star appears in the evening.

It seems that the sentence ‘the evening star appears in the evening’ is part of the larger sentence, (6). And it seems as if the phrase ‘the evening star’ is part of that contained sentence, and hence also part of the whole sentence (6). Moreover it is also true that the morning star is the same thing as the evening star; so the phrases ‘the morning star’ and ‘the evening star’, which are regarded by Frege as singular terms, refer to same thing. It might seem, then, that the following sentence must be true:

(7) Carol thinks that the morning star appears in the evening.

But surely she thinks no such thing.

Frege’s response to this problem is, in effect, to accept that the contained sentence ‘the evening star appears in the evening’ is part of the whole sentence (6), and to maintain that the reference of the whole sentence (6) depends on the reference its part –but to deny that in this context the parts have their normal reference. In contexts like this, Frege claimed, contained sentences and their parts have as their reference not their normal reference but their normal Sense. This means that you can only swap expressions contained in these contexts if they have the same Sense.

 

قسمت هفتم: پرسش‌هایی درباره‌ی Sense

Frege agrees with Locke on this point:

(L3) What language is meant to communicate is thought.

But he disagrees with him over the nature of thought.

The claim that Frege offers a fundamentally different account of communication from Locke’s depends on making it clear that Fregean Thoughts are fundamentally different from Lockean Ideas. There are several respects in which one might doubt whether it is as large as initially seems.

The first respect in which the difference between Lockean Ideas and Fregean Thoughts end up looking less than it might initially seem is that Fregean Thoughts seem more personal than his official account might suggest. The other respect in which it seems harder than it might have been thought to maintain a firm contrast between Fregean Sense and Lockean Ideas concerns the relation between Sense and reference.       

 

قسمت هشتم: Sense and Basic Worry

Frege introduced the notion of Sense in order to deal with what may be described as the basic worry with the view that the meaning of words concerns things in the world, rather than things in the mind. In its most general form, the Basic Worry is this. If what matters about the meaning of words is which things in the world are associated with them, we might expect two words which are associated with the same thing in the world to have the same meaning, and a word which is associated with no thing in the world to have no meaning. But it’s natural to think that this is wrong. The notion of Sense is introduced precisely in order to deal with this Basic Worry. We’ve seen that there are some difficulties with the notion of Sense: might we do without it?

 

قسمت نهم: منابعی بیشتر برای مطالعه

از فرگه:

1)      The Foundations of Arithmetic

2)      Thoughts

3)      Function and Concept

4)      On Concept and Object

درباره‌ی فرگه:

1)      Frege: A Critical introduction, H. Noonan

2)      Frege, A. Kenny

3)       Frege: Philosophy of Language, M. Dummett

4)      The Varieties of Reference, G. Evans