PHILOSOPHY OF LANGUAGE LECTURE PART 2

Transcription

1 PHILOSOPHY OF LANGUAGE LECTURE PART 2 FREGE, ON SENSE AND REFERENCE PROFESSOR JULIE YOO Puzzle of Empty Names Some Strategies: Meinong, Locke, Russell The Nature of Sense The Semantic Side of Sense The Epistemic Side of Sense Metaphysical Side of Sense Senses and Propositions ( Thoughts ) Puzzle of Indirect Contexts Belief Contexts and Substitutivity Fregean Thoughts and Truth Values Problems with Sense Frege Lecture Part 2.docx Part 2 Page 1 of 6

2 PUZZLE OF EMPTY NAMES If you are committed to a strict Reference Theory of meaning for proper names, then names like Santa Claus and Sherlock Holmes will have no meaning since they have no reference. But this is unintuitive. Though they have no reference, they still carry linguistic meaning. Some Strategies: Meinong, Locke, and Russell Meinong: Such names do denote objects, but they are non-existent objects. These objects have a different kind of existence: what Meinong calls subsistence. Locke: Such names denote an idea, which certainly exist, in our heads. This is not the Idea Theory, which reduces meanings to ideas. Here, ideas are the referent. Russell: They aren t names after all because genuine names can t fail to denote. Instead, they are definite descriptions expressions of the form, the so-and-so. Q4 Though these names lack a reference, they have meaning because they express a sense. Thus, a name can express a sense but have no reference. A Name Can Have A Sense and No Reference: The meaningfulness of an expression consists in its sense, not its reference. The sense is a criterion of identification for the referent; it just so happens that nothing in the world satisfies the criterion. From this, Frege argues that sentences containing empty names are neither true nor false. Such sentences, Frege claimed, have a role in literature and poetry the role of conjuring up images and arousing our emotions but they should have no role in science or mathematics. THE NATURE OF SENSE Semantic Side of Sense Frege s characterizations of sense are mostly metaphorical, but there are certain things we can glean from his writings. Compositionality: The sense of a complex expression is determined by the senses of its constituents. Substitutivity: Substituting one expression with another having the same sense will maintain the sense of the original expression. Normativity: Senses constrain the correct use of an expression. Frege Lecture Part 2.docx Page 2 of 6

3 The Epistemic Side of Sense The epistemic role of sense comes down to its role as a criterion of identification that can he grasped by the speaker how knows how to use the term. A Sense Is a Criterion of Identification: A sense determines the reference because the sense of an expression is a descriptive condition that uniquely singles it. The identifying feature has to supply a condition that is both necessary and sufficient for the individual it picks out; otherwise, it would fail to pick out a candidate at all or it would pick out too many candidates. Articulating the content of a sense, then, calls for a definite description. To Understand An Expression Is To Grasp Its Sense: Grasping the sense gives you the ability to identify the reference. These abilities are limited not only by what is given to you in the descriptive condition, but also by the fact that the descriptive conditions apply only in certain circumstances and contexts. After all, if the descriptive condition gave you everything concerning the object, then certain identifications (morning star and evening star) would never be surprising discoveries. Possible to Grasp the Sense But Not Know the Reference: This is the epistemic corollary to the semantic thesis that it is possible for a term to have a sense and no reference. The Metaphysical Side of Sense Frege also appeals to sense to explain how communication is possible. And it explains it by being objective. It is not a matter of associating it with an image or idea. Here is Frege s (informal) argument against the reduction of meaning to ideas: Sense as Objective: Q5 The sense of an expression is objective. Senses are not ideas, which are subjective. Senses are Abstract Objects: Senses cannot be identified with states of the mind, nor can they be identified with existing objects, since senses can be of non-existing things. They are like numbers in their non-physicality and objectivity. Senses and Propositions Sense of a Sentence Is a Thought: Q6 The sense of a sentence is a complex made up of the senses of its parts, and while it parts cannot take on a truth-value, the complex can. This is what Frege calls a thought. The Reference of a Thought Is a Truth Value: The reference of Earth has water is THE TRUE; the reference of Earth has unicorns us THE FALSE. Frege Lecture Part 2.docx Page 3 of 6

4 PUZZLE OF INDIRECT CONTEXTS Belief Contexts and Substitutivity The following kinds of expressions create what s called an indirect context (aka opaque, oblique, intensional, non-extensional context). John believes that John wants to date John was upset that John was wondering whether And names or sentences that would be filled in the line are sentences that occur within an indirect context. Indirect contexts appear to violate a true principle: Principle of Substitutivity (PS): If S is a complex expression with a certain reference (truth-value), and s is a part of S, then the replacement of s with a co-referring expression s* will yield a sentence S* that has the same reference (truth-value) as S. Here s an example involving sentences S The earth is round. T s the earth s* the third planet from the sun S* The third planet from the sun is round. T s and s* are co-referring expressions; in other words, they refer to the same individual. According to PS, if S is true, the S* will also be true. The expressions maintain their reference (truth-value) under substitution of co-referring expressions. However, when it comes to indirect contexts, PS seems to break down. But it seems to fail in a certain situation. Suppose John believes that the earth is round, but knows nothing about astronomy. O John believes that the earth is round. T o the earth o* the third planet from the sun O* John believes that the third planet from the sun is round. F O Lois Lane wants to date Superman. T o Superman o* Clark Kent O* Lois Lane wants to date Clark Kent. F Frege claims that the thought is the sense of a sentence. The reference of a sense, on the other hand, is its truth value. But if the argument above is right, and the thought is not the reference of a sentence, then what is it? Frege s view was that PS is not violated because co-referring Frege Lecture Part 2.docx Page 4 of 6

5 expressions that occur within an oblique context do not denote the references they denote when they occur directly. In other words, o and o* don t denote the same object denoted by s and s*. In a direct context, a name denotes its referent and expresses its sense; a sentence denotes / refers to a truth-value and it expresses a thought. In an indirect context, a name denotes the sense it expresses in a direct context; the reference of a proper name is its customary sense. And a sentence denotes the thought it expresses in a direct context; the reference of a sentence is its customary thought. IN EXTENSIONAL CONTEXTS DIRECTLY OCCURRING IN INTENSIONAL CONTEXTS INDIRECTLY OCCURRING NAME SENTENCE expresses a sense denotes a reference expresses a thought denotes a truth-value denotes its customary sense denotes its customary thought So because s and s* have different customary senses, they will serve as different referents when they occur indirectly as o and o*. So in moving from O to O*, we haven t actually substituted co-referring expressions, so we don t have a violation of PC after all. FREGEAN THOUGHTS AND TRUTH VALUES The foregoing discussion of the problem of belief contexts leads Frege to draw an important conclusion about the nature of what he calls thoughts. Q6: 1. The application of PS to S does not change its reference (t-v). 2. The application of PS to O does change the thought. 3. The thought is not the reference of a sentence. PROBLEMS WITH SENSE There are several problems with the notion of sense introduced by Frege. 1. There s no clear account of how we grasp the sense of an expression. 2. Senses don t explain the possibility of communication because two or more different senses can be attached to the same term. (Miller 43-44) 3. * Senses don t allow for the possibility of informative analyses because identity statements can be informative only if they involve different senses, but analyses involve terms expressing the same sense. (Miller 45-47) Frege Lecture Part 2.docx Page 5 of 6

6 4. * Frege s maneuver for the problem of opacity doesn t easily work for sentences in doubly indirect contexts: John believes that Mary believes that Cassius Clay is Muhammad Ali. (Miller 47-51) 5. * The idea that there can be sense but no reference, or that there can be a thought but no truth-value is dubious; reference and truth-value are those elements of an expression in virtue of which the expression is meaningful, but in the absence of these elements, it s hard to know how sense and thought can serve as the proper meaning surrogate. (Miller 51-52) Frege Lecture Part 2.docx Page 6 of 6