From: Keith Brown (ed.) The Encyclopedia of Language and Linguistics. Elsevier (2005). Object-dependent thoughts Sean Crawford University of Manchester Abstract The theory of object-dependent singular thought is outlined and the central motivation for it, turning on the connection between thought content and truth conditions, is discussed. Some of its consequences for the epistemology of thought are noted and connections are drawn to the general doctrine of externalism about thought content. Some of the main criticisms of the object-dependent view of singular thought are outlined. Rival conceptions of singular thought are also sketched and their problems noted. Some of our thoughts involve reference to particular individual entities. Philosophers call these kinds of thoughts 'singular thoughts'. Russell was a great philosopher, You're standing on my foot, I'm tired, That raccoon got into my garbage last night-these are all singular thoughts because each involves reference to a particular thing: Russell, you, me, and a certain raccoon, respectively. As these examples indicate, singular thoughts are usually expressed by sentences containing proper names (e.g., 'Russell'), indexicals (e.g., 'you' and 'I') and demonstrative expressions (e.g., 'that raccoon'). 2 1. Singular Thoughts as Object-Dependent Some philosophers maintain that singular thoughts are object-dependent, by which they mean that the intentional content of the thought essentially involves the object that it is about, in the sense that the thought content would not be available to a thinker were the object not to exist. More precisely, a singular thought is object-dependent just in case its content is such that: (1) its existence depends upon the existence of the object thought about; and (2) its identity depends upon the identity of the object thought about. For example, consider the thought, That raccoon got into my garbage last night, had by me while I am spying a particular raccoon skulking in my backyard. According to the doctrine of object-dependence, if, counterfactually, no raccoon had in fact been there to be singled out by me, owing perhaps to my delusional or hallucinatory state of mind-let us call this the "empty possibility"-then there would have been no singular thought content for me to entertain. Consequently, my psychological condition in this situation would be different from what it is in the actual situation. Moreover, if, counterfactually, my thought had singled out a qualitatively indistinguishable but numerically different raccoon instead-call this the "duplicate possibility"-then the resulting thought would have had a different content from the content which my thought has in the actual situation. Again, my overall psychological state in this duplicate possibility is different from what it actually is. The implication here for linguistic meaning is that the meaning of sentences containing genuine singular terms (e.g., proper names, indexicals and proper names) depends upon the singular terms in question successfully referring to objects. On this view, non-fictional sentences containing non-referring singular terms, such as empty or bearerless names, are meaningless, in the sense that they fail to express any thoughts. 3 The doctrine of object-dependence is a species of the more general doctrine of externalism about thought content, according to which some states of mind are such that we can be in them only if we bear certain appropriate relations to other things in our environment, and thus is opposed to internalism about the mind, according to which the contents of our thoughts are never dependent upon any relations between us and other things in our environment. (Some philosophers, such as Burge (1982), accept the general doctrine of externalism but reject object-dependence.) 2. Epistemological Consequences of Object-Dependence It is controversial which, if any, singular thoughts are object-dependent. Arguably, firstperson thoughts expressed with the indexical 'I' are object-dependent: it seems obvious that if I did not exist then the thought that I now express with the sentence 'I'm tired' could not exist; moreover, no one else could have had the very same thought. But the thesis that singular thoughts expressed with proper names and demonstratives are objectdependent has seemed paradoxical to some philosophers. For when the idea of objectdependence is applied to these other types of singular thoughts, it runs up against a strongly held intuition about the nature of thought content: namely, that we have a kind of direct, non-inferential knowledge of the contents of our thoughts, in the sense that we know, just by thinking, whether we are having a thought and, moreover, what thought we are having. The doctrine of object-dependence seems to contravene this intuition about the epistemology of thought. For, first of all, condition (1) above allows the possibility that a thinker could suffer the illusion of entertaining a thought when he was not in fact doing so. If, unbeknown to 4 me, I am in what we have been calling an empty possibility and am hallucinating a raccoon rather than actually seeing one, it may seem to me that I am having a singular thought, which I might try to express with the sentence 'That raccoon got into my garbage last night', even though I am not. But is this kind of cognitive illusion really possible? It is very tempting to think, against this, that if it seems to me as if I am having a thought with a certain content, then I am. Perhaps I might be mistaken about which object, if any, my thought is about-but how could I be mistaken about whether I was even thinking a thought at all? Condition (2) has also seemed problematic. Consider what we have called the duplicate counterfactual possibility in which I see a different raccoon, qualitatively indistinguishable from the one I actually see, and think That racoon got into my garbage last night. In such a case, everything will seem the same to me: the duplicate raccoon does not appear to affect my conscious awareness in any way different from how the actual raccoon affects it. But is not subjective indistinguishability the criterion for sameness and difference of thought content? Opponents of object-dependence argue that in order for there to be a genuinely psychological or mental difference between the two cases this difference must impinge upon my conscious awareness in some way. The object-dependent theorist denies this, arguing that it is the product of a mistaken internalist picture of the mind, a picture that the object-dependent theorist urges us to reject in favour of an externalist view. The debate between object-dependent theorists and their opponents is thus linked to a certain extent to the larger debate between internalism and externalism about thought content. 5 3. The Central Motivation for Object-Dependence A number of different considerations have been advanced in favour of an objectdependent conception of singular thought, and many involve a synthesis of key ideas of Frege and Russell (Evans 1982; McDowell 1977, 1984, 1986; and McCulloch 1989). Advocates of this form of object-dependence are often labelled 'neo-Fregeans', which can be confusing, because object-dependent singular thoughts are also often called 'Russellian thoughts'. So one needs to be aware of differing terminology here. Perhaps the best way to appreciate the object-dependent theorists' point of view is to begin by noting that they do countenance thoughts that in a certain sense concern particular individuals but which would be available to a thinker were those individuals not to exist. Moreover, there is a straightforward sense in which the contents of these kinds of thoughts would remain unaffected were duplicate objects substituted for the actual ones. Calling these kinds of thoughts object-independent thoughts, we can say that although they concern particulars, the relation between their contents and their objects is much less "direct" or "intimate" than the relation between the contents and objects of object-dependent thoughts (the idea goes back to Russell's (1910-11) seminal distinction between knowledge by description and knowledge by acquaintance). The most obvious examples of object-independent thoughts are thoughts that involve definite description concepts, thoughts of the form 'The F is G'. Consider the thought The first man on the moon was an American. As it happens, this thought is about Neil Armstrong because he was in fact the first man on the moon. But consider now the empty possibility in which the lunar landing was a hoax and the definite description 'the first man on the moon' fails to designate anything. The object-dependent theorist holds that 6 despite the fact that the thought fails to single out any actual object in the world, the thought still has a content, a content expressed, in part, by the definite description. Similarly, consider the duplicate possibility, in which Neil Armstrong's identical twin is the first man on the moon. Despite the thought's picking out a different man, the content of the thought remains the same-again, that expressed (in part) by the definite description 'the first man on the moon'. The crucial point here is that the intentional content of the thought can be specified independently of the object, if any, that it is about. The object-dependent theorist's idea is this. Thought content is essentially representational: it represents the world as being a certain way; it lays down conditions that the world must meet in order for the thought to be true. That is to say, the content of a thought determines its truth conditions. In the case of a thought employing a definite description concept 'the F' (a descriptive thought, for short) the thinker knows what those conditions are without knowing which object, if any, the thought concerns. If I say to you 'The first man on the moon was American', it is not necessary for you to know which object is the first man on the moon, nor even that there is such an object, in order for you to understand what I have said, in order for you to "grasp" the thought I expressed with this sentence. So long as you understand all the words in the sentence and their mode of combination you know exactly how the world is represented as being; you know what the thought is "saying" about reality. In other words, you know that the thought is true just in case there is a unique man who was first on the moon and who was American. It does not matter who this man happens to be-Neil Armstrong, his identical twin, or Buzz Aldrin. So long as there is such a man the thought is true; and if there is no such man-either because no man at all has ever been on the moon or because more than one man stepped 7 onto the moon at exactly the same time-then the thought is false. The representational content of a descriptive thought is thus independent of any object that the content might be about. The truth conditions make no reference to any man in particular. When it comes to singular thoughts, however, the object-dependent theorist maintains that their representational content is not independent of any object the content is about. On the contrary, the content requires that a certain particular object be picked out. In order to understand or grasp the though in question one must know which particular object this is. Consider the foregoing example of a singular thought: That raccoon got into my garbage last night, based on my visual experience of a particular raccoon in my backyard (these kinds of singular thoughts are sometimes called 'perceptual demonstrative thoughts'). Now, in having this thought, I am representing the world in a certain way. What way is this exactly? Well, I am not representing the world as merely containing a raccoon that got into my garbage last night, whichever raccoon that might be. No: the way I am representing the world as being involves that very raccoon. My thought is true just in case that raccoon (the very one I saw) got into my garbage last night; and in order for you to have this thought too, you need to know which particular raccoon is singled out by my perceptual demonstrative 'that raccoon'. Contrast this with the very different case where I think the descriptive thought The cleverest and boldest racoon in the neighbourhood got into my garbage last night. All that it takes for this thought to be true is for there to be a unique raccoon, who is cleverer and bolder than all the rest, and who got into my garbage-and you can grasp this thought without knowing which raccoon, if any, that was. If it turns out that there was no such raccoon, then my thought is straightforwardly false. But the truth conditions for my perceptual 8 demonstrative thought make essential reference to the very object it is about. The truth and falsity of this thought of mine turns on the condition of a particular raccoon, namely, that raccoon-so that if there is no such creature, if (say) I am hallucinating, there is nothing in the world to count as my thought being true or false. Consequently, in this empty possibility, my mental episode, whatever exactly its nature, has no truth conditions (for, to repeat, there is nothing of which I have judged to have a certain property; nor have I made the mere existential claim that there is an object with a certain property). Since thought content is essentially truth-conditional, according to the object-dependent theorist, I have not in fact had a singular thought at all, only the illusion of one. Whether considerations like these in favour of object-dependence apply equally to other kinds of singular thoughts, such as those expressed with proper names and indexicals (other than 'I'), is a further question. 4. Criticisms and Rivals Various criticisms have been levelled at the object-dependent conception of singular thought. Some of these arise from problems that the conception inherits from the general doctrine of externalism, such as its apparent conflict with certain features of selfknowledge (Davies 1998). Three issues, however, stand out with respect to objectdependence in particular. The first is the question of what is going on, psychologically speaking, in the minds of deluded subjects in empty possibilities who suffer the illusion of entertaining singular thoughts. Their minds are not phenomenological blanks, after all; yet, according to the object-dependent theorist, they are not filled with any singular thoughts. Are such 9 deluded subjects having any thoughts at all? If so, what kinds of thoughts are they having? The second issue is closely related to the first and concerns the commonsense psychological explanation of the actions of deluded subjects. Normally, we explain agents' actions-my charging into the backyard, say-by attributing singular thoughts to them-the belief that that raccoon got into my garbage last night, for example. But now consider my deluded duplicate who, after hallucinating a raccoon in the empty possibility, engages in the very same type of behaviour of charging into the backyard. According to the object-dependent theorist, my duplicate here has no singular thought; that is, he has no belief the content of which is That raccoon got into my garbage last night. But, although he is hallucinating, his action is perfectly rational, and so is presumably psychologically explicable by ordinary commonsense standards. But how do we so explain his behaviour without attributing a singular thought to him? (McDowell 1977; Segal 1989). Moreover, if we can explain his behaviour without attributing a singular thought to him, then why can we not do the same with me in the actual situation? But if we can do this with me too, then it looks like the ascription of object-dependent singular thoughts is "psychologically redundant"-and that allegedly calls into question their very existence (Noonan 1986, 1991; Segal 1989; Crawford 1996). The third issue, perhaps the most serious, is that there are powerful rival objectindependent conceptions of singular thought, which are free of many of the problems that beset object-dependent theories. There tend to be two different kinds of alternative conceptions. 10 The first of these attempts to analyze singular thought content in wholly general or descriptive terms, in such a way that the same content can exist in duplicate and empty possibilities, in the manner of thoughts involving definite description concepts, discussed earlier (Schiffer 1978; Searle 1983, 1991; Blackburn 1984, chapter nine). For example, we might try to analyze the content of the demonstrative expression 'that raccoon' as equivalent to the content of the definite description 'the raccoon I am seeing now' or 'the raccoon causing this visual experience'. The second approach opposes this kind of descriptive reduction and maintains a genuinely singular conception of singular thought, but argues that a distinction between irreducibly singular (or "de re") content and object can still be drawn; again, in such a way that, as with the first alternative, the same singular content can exist in both duplicate and empty possibilities (Burge 1977, 1982, 1983, 1991; Bach 1987; Segal 1989). This approach exploits an analogy between the semantics of sentences containing demonstratives and pronouns ('This is red', 'She is tall') and the semantics of the open sentences of a logical system ('x is red', 'x is tall')-namely, that both kinds of sentences are true or false only under an assignment of values to the demonstratives, pronouns and free variables in question. The proposal is to treat a sentence such as 'That is a raccoon' as like a predicate, or open sentence in the logician's sense, and to think of it as expressing a single content (a propositionally "incomplete" content) that is mentally applied, in different situations, to different objects, and even, in some situations, to no object at all. These two alternatives each face their own difficulties, however. The first alternative seems to over-intellectualize thinking. When I think That raccoon got into my garbage 11 last night I do not appear to be thinking about myself or the present moment or about causation or my own visual experiences; and even if I were doing so in a philosophical mood, it does not seem necessary for a creature to have such sophisticated concepts in order for it to have singular thoughts (McDowell 1991; Burge 1991; Searle 1991). As for the second alternative, it is not clear to what extent it departs from the intuitive principle that thought content is fully representational in the sense of always determining truthconditions. For in the empty counterfactual possibility, in which I hallucinate a raccoon, no value will be assigned to the demonstrative concept in my thought ('that raccoon') and hence no truth conditions for the overall thought will be determined. The advocates of this second alternative approach thus seem committed to the view that I can have thoughts that possess no truth conditions, something that may give us pause. Bibliography Bach, Kent. 1987. Thought and Reference . Oxford: Clarendon Press. Beaney, Michael, ed. 1997. The Frege Reader. Oxford: Basil Blackwell. Blackburn, Simon. 1984. Spreading the Word. Oxford: Clarendon Press. Burge, Tyler. 1977. 'Belief De Re'. Journal of Philosophy 74: 338-62. - 1982. 'Other Bodies'. In Andrew Woodfield (ed.) Thought and Object. Oxford: Clarendon Press. - 1983. 'Russell's Problem and Intentional Identity'. In James Tomberlin (ed.) Agent, Language, and the Structure of the World. Indianapolis: Hackett. - 1991. 'Vision and Intentional Content'. In Lepore and Van Gulick. Carruthers, Peter. 1987. 'Russellian Thoughts'. Mind 96: 18-35. 12 Crawford, Sean. 1998. In Defense of Object-Dependent Thoughts. Proceedings of the Aristotelian Society 98 (2): 201-10. Davies, Martin. 1998. 'Externalism, Architecturalism, and Epistemic Warrant'. In Crispin Wright, Barry C. Smith, and Cynthia Macdonald (eds.) Knowing Our Own Minds. Oxford: Clarendon Press. Evans, Gareth. 1982. The Varieties of Reference. Ed. John McDowell. Oxford: Clarendon Press. Frege, Gottlob. 1892. 'On Sinn and Bedeutung'. Trans. Max Black. In Beaney. - 1918. 'Thought'. Trans. Peter Geach and R. H. Stoothoff. In Beaney. McCulloch, Gregory. 1989. The Game of the Name. Oxford: Clarendon Press. McDowell, John. 1977. 'On the Sense and Reference of a Proper Name'. Mind 86. - 1984. 'De Re Senses'. Philosophical Quarterly 34: 283-94. - 1986. 'Singular Thought and the Extent of Inner Space'. In Philip Pettit and John McDowell (eds.) Subject, Thought and Context. Oxford: Clarendon Press. - 1991. 'Intentionality De Re'. In Lepore and Van Gulick. Noonan, Harold. 1986. 'Russellian Thoughts and Methodological Solipsism'. In Jeremy Butterfield (ed.) Language, Mind, and Logic. Cambridge: Cambridge University Press. - 1991. 'Object-Dependent Thoughts and Psychological Redundancy'. Analysis 51: 1-9. Russell, Bertrand. 1910-11. 'Knowledge by Acquaintance and Knowledge by Description'. Reprinted in Mysticism and Logic. London: George Allen and Unwin, 1917. - 1912. The Problems of Philosophy. Oxford: Oxford University Press. - 1918. 'The Philosophy of Logical Atomism'. In Logic and Knowledge. London: George Allen and Unwin, 1956. Schiffer, Stephen. 1978. 'The Basis of Reference'. Erkenntnis 13: 171-206. Searle, John. 1983. Intentionality. Cambridge: Cambridge University Press. - 1991. 'Response: Reference and Intentionality'. In Lepore and Van Gulick. 13 Segal, Gabriel. 1989. 'The Return of the Individual'. Mind 98: 39-57. Suggested Cross References externalism about content; descriptions, definite and indefinite, philosophical aspects; two-dimensional semantics; empty names; proper names, philosophical aspects; immunity to error through misidentification; dthat; Frege; Russell; counterfactuals; indexicality, philosophical aspects; truth conditions and meaning; reference, philosophical theories. Key words object-dependent thought, singular thought, descriptive thought, intentional content, thought content, mental representation, truth conditions, externalism, internalism, definite description, Frege, Russell, indexicals, demonstratives, proper names, action explanation. Biography Sean Crawford has a BA from Simon Fraser University, an MA from Dalhousie University, and a DPhil from the University of Oxford. He teaches philosophy at University of Manchester and is the author of several articles on the philosophy of mind and philosophy of language.