Word and Object is a 1960 work by the philosopher Willard Van Orman Quine, in which the author expands upon the line of thought of his earlier writings in From a Logical Point of View (1953), and reformulates some of his earlier arguments, such as his attack in "Two Dogmas of Empiricism" on the analytic–synthetic distinction.^[1] The thought experiment of radical translation and the accompanying notion of indeterminacy of translation are original to Word and Object, which is Quine's most famous book.^[2]

Quine emphasizes his naturalism, the doctrine that philosophy should be pursued as part of natural science.^[3] He argues in favor of naturalizing epistemology, physicalism as against phenomenalism and mind-body dualism, and extensionality as against intensionality. He also develops a behavioristic conception of sentence-meaning, theorizes about language learning, speculates on the ontogenesis of reference, explains various forms of ambiguity and vagueness, and recommends measures for regimenting language so as to eliminate ambiguity and vagueness as well as to make a theory's logic and ontic commitments perspicuous ("to be is to be the value of a bound variable"). He argues, moreover, against quantified modal logic and the essentialism it presupposes, argues for Platonic realism in mathematics, rejects instrumentalism in favor of scientific realism, develops a view of philosophical analysis as explication, argues against analyticity and for holism, against countenancing propositions, and tries to show that the meanings of theoretical sentences are indeterminate and that the reference of terms is inscrutable.^[4]

Central to Quine's philosophy is his linguistic behaviorism. Quine has remarked that one may or may not choose to be a behaviorist in psychology, but one has no choice but to be a behaviorist in linguistics.^[5]

This influence can be seen in Word and Object. In chapter 2 a linguist has to translate a native's unknown language into English. What is so specifically behavioristic there is that the linguist has nothing to go on but verbal behavior from the native and the visible environment the native interacts with. The same view is displayed in chapter 3 where Quine describes how a baby learns its first words. In this chapter Quine also mentions B.F. Skinner, a well known behaviorist, as one of his influences. The opposite view to Quine's and Skinner's in philosophy of language is represented by Noam Chomsky's linguistic nativism.^[6]: 73

In the second chapter of Word and Object, Quine investigates the concept of meaning. He shows to what extent his own, empirical, notion of meaning can give an account for our intuitive concept of meaning: 'what a sentence shares with its translation'.^[6]: 29 Quine also introduces his famous principle of indeterminacy of translation, with the help of the thought experiment of radical translation, i.e. translation of a hitherto unknown language (called Jungle by Quine) into English. The point of this thought experiment is to show that a behavioristic account of meaning does not allow for the determination of the right manual for translating one language into another, as there is no such single right translation manual.^[7]

A linguist desiring to translate Jungle has to set up his translation manual based only on the events happening around him/her, the stimulations, combined with the verbal and non-verbal behaviour of Jungle natives.^[8] The linguist can thus only use empirical information, therefore, radical translation will tell us which part of our language can be accounted for by stimulus conditions. In the experiment, Quine assumes that functional Jungle equivalents of 'Yes' and 'No' are relatively easy to be found. This allows the linguist to actively query the utterances of the natives, by repeating words (s)he has heard the native utter, and to subsequently record the native's reaction of assent or dissent.

In determining the translation of the Jungle sentence 'Gavagai' (whose English equivalent would be 'Look, a rabbit'), the linguist first has to determine which stimulation prompt the native to assent, and which prompt him to dissent to the linguist uttering 'Gavagai'. For example, if the linguist sees a rabbit, and the native says 'Gavagai', the linguist may think that 'Gavagai' means 'Rabbit'. (S)he will then try the sentence 'Gavagai' in different situations caused by the stimulation of a rabbit, to see whether the native assents or dissents to the utterance. The native's reaction is elicited by the linguist's question and the prompting stimulation together. It is the stimulation that prompts the assent or dissent, not the object in the world, because an object in the world can be replaced by a replica, but then the stimulation stays the same. 'The class of all the stimulations [..] that would prompt his assent'^[6]: 29 is the affirmative stimulus meaning of a certain sentence for a given speaker. Negative stimulus meaning is defined likewise, with assent and dissent interchanged. Quine calls these affirmative and negative stimulus meaning combined the stimulus meaning of the sentence. However, since we want to account for the fact that a speaker can change the meaning of a concept, we add the modulus to the definition of stimulus meaning: the time frame in which the stimulations take place. Once the stimulus meaning has been found, the linguist can then compare it to the stimulus meanings of sentences in English. The English sentence with (near-) identical stimulus meaning to 'Gavagai' functions as a translation of 'Gavagai'.

After Quine has set out the concept of stimulus meaning, he continues by comparing it with our intuitive notion of meaning.^[9]: 100 For this, he distinguished two kinds of sentences: occasion sentences and standing sentences. Occasion sentences are the sentences that are only affirmed or dissented after an appropriate stimulation,^{[6]: 32–33} e.g. 'Look, a rabbit walks by!' On the other hand, there are standing sentences, which do not rely on stimulation for assent or dissent; they can be prompted by stimulation, but they don't have to be, e.g. 'Rabbits are mammals'. Thus, the stimulus meaning is less useful to approximate the intuitive meaning of standing sentences. However, the difference between occasion and standing sentences is only a gradual difference. This difference depends on the modulus because 'an occasion sentence modulo n seconds can be a standing sentence modulo n – 1'.^[6]: 32

Since stimulus meaning cannot really account for the intuitive concept of meaning for standing sentences, the question remain whether it can account for the intuitive concept of meaning for observation sentences. Quine approaches this question by investigating whether, for occasion sentences, the intuitive notion of synonymy (sameness of meaning) is equivalent to the notion of stimulus synonymy (sameness of stimulus meaning).^[9]: 100 For this question, he uses the notion of observationality. A special subclass of occasion sentences are the observations sentences. Their stimulus meaning is least influenced by collateral information, extra information that is hidden for the linguist, and does not vary over the population. Therefore, observation sentences belong to the sentences that are directly translatable by the linguist.^[10] However, it is exactly this point of collateral information that poses problems for equating the intuitive notion of synonymy with the notion of stimulus synonymy. For even sentences that are supposedly highly observational, like 'Gavagai!', can be affected by collateral information. Quine uses the example of a rabbit-fly: assume that there is a fly that is unknown to the linguist, that only occurs in the presence of rabbits. Seeing such a rabbit-fly in the grass would thus make the native assent to the sentence 'Gavagai', because the native can be sure that there is a rabbit nearby. However, the rabbit-fly is not part of the stimulus meaning of 'Rabbit' for the linguist. Thus, even for the most observational occasion sentences, it is not possible to equate the intuitive notion of synonymy with stimulus synonymy. From this, Quine concludes that we cannot make sense of our intuitive notions of meaning. As Becker formulates it:

From Quine's perspective, the conclusion to be drawn from our failure to reconstruct intuitive semantics is not that the attempt was misconceived but that our ordinary notions about meaning cannot be made intelligible. More particularly, intuitive semantics is committed to a distinction—between semantic information, information about meanings, and factual (or collateral) information, information not about meanings—which we cannot make sense of even in the case of sentences like 'Rabbit', let alone for sentences in general.^[9]: 109

In Chapter 2 of Word and Object, Quine shows that the total apparatus of grammatical and semantic devices in a language is not objectively translatable into foreign languages. Therefore, in Chapter 3, he proposes to investigate a language's devices relative to each other. For this, he first describes a child's process of acquiring reference, by showing the order in which children learn grammatical devices. In Chapter 4 he then turns away from language acquisition, to investigate the vagaries of reference in a particular language (English). In Chapter 5, Quine proposes a system for regimentation, which should help us understand how reference in language works and should clarify our conceptual scheme. He calls this system the canonical notation; it is a system with which we can investigate the grammatical and semantic devices of English by paraphrase.

In the last section of Word and Object,^[6]: 56 Quine asks the question why, in a book titled Word and Object, we have talked more about words than about objects. He comes to the conclusion that this has to do with the distinction Rudolf Carnap makes between a material mode of speech and a formal one.^[13] In the material mode we talk about objects themselves and usually this is unproblematic. However, when two people with completely different ideas of whether or not there are such entities as miles, are discussing miles as the objects themselves this discussion will be fruitless. It is in these instances that we see what Quine calls semantic ascent,^{[6]: 249–254} the shift from the material mode of language to the formal one. In the formal mode of language we are at a different level. Rather than talking about miles as objects we are talking about what this word 'mile' even means, what it refers to and if it even refers at all. In the formal mode, people with different conceptual schemes might be able to have a reasonable discussion because they are talking about something their conceptual schemes have in common: language.

Quine differs from Carnap in applicability of semantic ascent.^[6]: 250 Carnap believes that talking in a formal mode is something that can only be done to some effect in philosophy. Quine, however, believes that semantic ascent is used in science as well. He argues that Einstein's theory of relativity wasn't just accepted by the scientific community because of what it had to say about 'time, light, headlong bodies and the perturbations of Mercury'^[6]: 251 in the material mode, but also because of its simplicity compared to other theories in the formal mode. The formal mode allows for a more distant approach to certain problems; however, we are not able to reach a vantage point outside of our conceptual scheme, to Quine 'there is no such cosmic exile'.^[6]: 254

• American philosophy
• Indeterminacy of translation
• Neurath's boat – a philosophical analogy popularized by Word and Object
• Radical translation