The contemporary debate on the nature of semantic content looks, at least from afar, like a battle between two armies. On the one hand, one finds the externalists, who claim that the content of what you have in your head depends on what's out there in the world. For example, the content of my concept of water is determined by the substance in the world that instantiates it, while the content of my thoughts about arthritis is dependent on the social conventions of my community. Internalists, on the other hand, have ‘pushed the world into the mind’ (to borrow Ray Jackendoff's phrase) and hold that it is the compositional and/or inferential nature of conceptual representations that determine their content.

Curiously, the defenders of externalism seem to come largely from a philosophical background, while linguists often opt for the internalist explanation. Wolfram Hinzen, who is a professor of philosophy at the University of Durham, but works within the biolinguistics program, seems to be the ideal person to rejuvenate this sometimes gridlocked debate.

Hinzen's latest book, An essay on names and truth, is part of an ambitious venture in which the author aims to invalidate the central intuitions behind externalism, while at the same time arguing for a type of internalism that has next to nothing in common with comparable theories on the market. Hinzen takes as a starting point two traditional strongholds for externalist theories of meaning: names, ‘the very paradigm of a referential expression’ (2), and truth, which few theorists would dare suggest have nothing to do with the external world. His central idea is that the judgements of truth we make are dependent on the syntax that underpins thought, and that names, like all other expressions, get their content from their syntactic form.

Holding that proper names refer to objects in the world and that mind-internal ideas are causally linked to external properties is an empiricist illusion conception, which has become philosophical deadweight with the emergence of modern linguistics, according to Hinzen. In his view, ‘[m]uch human thought is not really directed at the external world, involving abstract objects instead that have no perceptual dimensions to them, such as fairness, joy, social progress, numbers, or truth’ (13). Externalist semantics, ‘which is a behaviourist heritage’ (78), needs to be replaced by a program that takes seriously the insights from developments in generative grammar. Yet, the failure of the generative semantics program has shown us that most word meanings cannot be decomposed into smaller entities or reduced to a series of inferential relations. The author holds that the only solution to this paradox lies in adopting internalist atomicity, according to which concepts are empty and unstructured, but get their content from syntax.

Hinzen is aware that he is navigating treacherous waters here, and takes great care with the exposition of both the views he endorses and those he argues against. He gives a clear and concise overview of the main topics of discussion, although his style throughout is both polemical and confrontational. His book, which forms part of the Oxford Linguistics list, is aimed at readers familiar with key concepts in generative grammar, but presupposes little knowledge of philosophy of language.

The book consists of five chapters, in which the author tackles the perceived obstacles for an internalist theory of meaning one by one, as well as posing a series of challenges to his externalist and non-atomistic opponents. Chapter 1, ‘Roots of the intentional’, sets out the central motivations behind Hinzen's research program, and picks up the thread from his previous book (Hinzen Reference Hinzen2006), in which he argued that meaning arises in the mind as a consequence of formally designed structures. Hinzen holds that syntax needs to be at the forefront of all studies of meaning, since the alternative – a semantic-pragmatic notion of ‘what is said’ – is not a natural object and therefore not a possible focus of naturalistic enquiry (42).

In chapter 2, ‘Where meaning begins: The atoms of thought’, Hinzen pursues this line of thought further. He maintains that externalism as a theory suffers from an inherent lack of explanatory adequacy, since there is no way to specify what a concept means without appealing to notions that the concept itself expresses. In his view, maintaining that house means/expresses the property house gets us no way towards explaining how semantics works, while the philosopher's idea of reference, which he sees as ‘the most paradigmatic attempt to explicate the content of a conceptual atom relationally’ (77), is equally problematic.

Chapter 3, ‘Structures for concepts’, sees Hinzen direct his attention towards the claim that concepts are atomic entities that cannot be decomposed or reduced to a series of inferential relations. He concludes, with Fodor (Reference Fodor1998), that all attempts at decomposition have failed and that the other available internalist accounts of semantics are essentially a continuation of the generative semantics enterprise. Contra Fodor, Hinzen argues that this does not entail giving up on an internalist notion of meaning, and he proceeds to set out his own approach, in which meaning originates from argument structure and thematic roles – phenomena that he regards as syntactic in origin. Following a suggestion by Hale & Keyser (Reference Hale and Keyser2002), he identifies theta-roles with certain phrase-structural configurations (138), arguing that it is syntax that fuels understanding of individual linguistic expressions, and that this undermines the syntax/semantics divide held sacred by other internalists, such as Ray Jackendoff (see, for example, Jackendoff Reference Jackendoff2002).

In the final two chapters of the book, Hinzen expands on his suggestions and develops an internalist account of truth and names. In chapter 4, ‘Structure for truth’, he investigates, ‘as in a piece of “ordinary language philosophy”’ (202), the meaning of the lexical item true in use, ‘and the specific structures in which this particular lexical concept appears’ (202). He concludes that truth does not seem to be understood as a relational concept (169) but needs to be seen in syntactic terms.

In chapter 5, ‘Structure for names’, Hinzen provides a number of examples designed to bring into question the externalist nature of nominal reference. He argues that the external existence of a referent makes no difference to our concepts of Tyson or Hamlet, and that the Kripkean notion of rigidity, which he sees as the outcome of a causal theory of reference, has to be rethought in syntactic terms. Hinzen suggests treating names as nouns with covert classifiers at the level of sub-lexical syntax, encoding ‘slots’ for, among other things, mass, mode and type. This allows him to treat examples such as 0–0, which he considers to be tricky for causal reference theories of names, without appeal to ‘beliefs, world knowledge, or pragmatics’ (217).

1. (1) Much Tyson remains to be re-discovered. (208, ex. (1g))

2. (2) Yesterday's Tyson was a disappointment. (208, ex. (1c))

3. (3) Marias are usually good girls. (226)

But Hinzen's proposal leaves the reader with many more questions than answers. He does not really manage to explain away the intuitions that concepts get their content from something outside the head: there clearly has to be more to proper names like Gödel, Tyson and London than their underlying syntactic structure, which is the same in all three cases. If this syntactic information is not supplemented by information from other cognitive domains, the internalist is left with no way to explain how Tyson picks out Tyson and not Holyfield or Madonna, or any other object that satisfies the constraints imposed by Hinzen's theory. The same goes for verbs and other word classes. If argument structure and thematic roles exhaust conceptual content, what is it that explains the difference in meaning between ‘buy’ and ‘sell’, ‘cut’ and ‘open’, ‘green’ and ‘red’ – or even ‘chimney’ and ‘sponge’?

In an online discussion predating his book, Hinzen (Reference Fodor2007) allows for the option to let his ‘internalist story … be “supplemented” by another one’, but nowhere in An essay on names and truth does he discuss how this might happen. On the contrary, he readily concedes to being deeply pessimistic about the prospects of his research program, which is a somewhat paradoxical position, given that his main accusation against externalism is its presumed lack of explanatory adequacy. Discussing justice, Hinzen states that ‘[i]t might be the internal structure of this concept, if it has one, is just not transparent for a mind like ours in the present state of its evolution’ (160). Though an analysis of the generative principle of number is already available, there is no imminent hope of coming up with a syntactico-semantic theory of house, ‘which is already much too complex’ (161). Instead of the naturalistic enquiry he advocates throughout, he is here perfectly content to delegate the work of finding the conceptual content of such words to the strictly non-naturalistic fields of hermeneutics and history of ideas.

For all its promises of a brand new day in the sometimes frustrating study of semantics and conceptual content, Hinzen's concession here takes the wind out of his sails. Restricting the scope of modern semantic theory to the treatment of an extremely limited set of words, consisting mainly of verbs as well as some nouns, adjectives and names that cannot be differentiated from one another, is hardly likely to attract hordes of students interested in meaning. This is especially disappointing considering Hinzen's high aims and his ambition to capture truth with such a limited conception of semantics. His analysis works well for certain aspects of the sentences he discusses, but his data are extremely narrow and idealized. Chapter 4, which claims that factual sentences come equipped with an integral expectation of truth, disregards the pervasive phenomenon of approximation and loose talk, where what is communicated departs from a norm of literal truthfulness. Since truth is held to be derived from syntax, a discussion of how one can give truth-judgements on sub-sentential utterances (such as John's father, uttered when pointing towards a man coming into the room) or non-linguistic communication would also have been welcome.

On the whole, Hinzen's essay fares a lot better in raising potential problems for other accounts than in providing positive solutions to these problems. When he complains that the referential relations presumed by philosophers to hold between names and the world are too seldom questioned or discussed, he is absolutely right. Defenders of externalism need to say more about how meaning is constituted in the referential relation, and in what way this works in actual communication. As a result, Hinzen raises important issues to be dealt with by any externalist, and his challenges should be vitalizing for the debate as a whole. But in the end, the externalist need not be too worried, since Hinzen's views of what this philosophical thesis is committed to prove to be much too narrow. He seems to equate the properties that an externalist sees as providing the content of concepts with physical ones, but this need clearly not be the case. An externalist like Jerry Fodor is perfectly happy to treat properties like Tuesday, fast or a convincing argument as providing the content of concepts (Fodor Reference Fodor1998: 149), since he emphasizes that perceptual mechanisms are not the only way to mediate between a mental item and the corresponding property.

The other problems that Hinzen raises for externalism can to a great extent be solved by letting pragmatics do more work. There are already theories which show how the use of proper names as generic and mass quantifiers may be fruitfully looked at as the outcome of a pragmatic process (see, for example, Wilson Reference Hale and Keyser2003), as well as solid explanations of how relational elements get their content independently of syntax (Carston Reference Carston, Davis and Gillon2004). It is not clear to me why Hinzen holds a notion of ‘what is said’ to be an unworthy object of study for naturalistic enquiry. Underlying this book, there seems to be something of a prejudice towards non-formal explanations in language-related matters. It is of course a methodological issue whether it is better to treat names as encoding complex sub-lexical syntax or whether one should favour an explanation that lets other cognitive capacities do the work, but by leapfrogging this whole issue, Hinzen misses a chance to convince those readers who do not a priori share his conviction that a syntactic explanation should always be preferred. This is a shame, since An essay on names and truth stands out as a daring project which poses a major challenge to all exponents of externalism, defenders of the Language of Thought hypothesis, non-atomistic internalists, and generative grammarians who want to preserve the autonomy of syntax. It is, all in all, a well-structured, well-written book that succeeds in putting all the fundamental issues for a theory of meaning on the table, and as such it cannot be ignored either by opponents to Hinzen's approach or by those who are curious about the scope and limitations of syntax-driven theories of meaning.