Philosophy of language is a familiar domain for philosophers. Philosophy of linguistics, conversely, is a field of study into which few of them venture, if only on account of its amalgamated nature: it can only fruitfully be explored if one has gained sufficient knowledge of both philosophy and linguistics. Given these two observations, there are two challenges for the author: ensuring that the book is accessible and that it pays due attention to the topics one may expect it to cover.

The Philosophy of Linguistics has a wide ambit, in spite of its length. Since the book covers a large number of topics, which are considered in passing rather than analyzed in detail, which might lead to arbitrariness in the selection of the aspects that are to be assessed, this review will limit itself, after the contents will have been outlined, to determining whether these two goals are realized.

The study consists of six parts: a brief introduction and five chapters (numbered 2 to 6). In the introduction, the author identifies the aim: “[…] asking what developments in the philosophy of linguistics can offer to the philosophy of science itself.” (p. 1). The chapters cover the following subjects. Chapter 2, “The ‘Science’ of Linguistics”, reflects on linguistics in relation to other sciences, first considering the philosophy of cognitive science, in which, not surprisingly, generative grammar, and the views of Noam Chomsky, arguably the most important and influential linguist of the previous century, feature prominently, which the author, however, rightly complements by alternative perspectives; Chomsky is – understandably – often referred to throughout the rest of the book as well. Subsequently, the philosophy of social science and of biology receive attention; the philosophy of biology focuses on salient aspects of biolinguistics.

The connection with social science is justified by pointing out that “Many philosophers of language have recognised the central place of communication with their focus on ordinary language, externalism, reference, and [conventionalism].” (p. 11), referring to the fields of sociolinguistics and pragmatics, while pointing to the fact that observations from such domains are not universally deemed linguistic stricto sensu. Indeed, linguistics may be identified with theoretical linguistics (with the subfields syntax, semantics (which is, of course, also a significant field of study of philosophy of language, for which reason it may, incidentally, be excluded from the purview of linguistics (Cf. Chomsky 1995, 24–26)), phonology (and possibly phonetics) and morphology), so that research in fields like sociolinguistics and psycholinguistics is only indirectly concerned with linguistics, on a multidisciplinary basis. Which view one is willing to accept is not a vital issue, however, since the very distinction between (sub)domains is a matter of convention, at least to some degree, especially if one explores the idea of considering linguistics as a social science (p. 13, 14). This issue will be revisited below.

Chapter 3, “Conduits to the General Philosophy of Science”, focuses on “[…] how issues within the philosophy of linguistics either exemplify, offer case studies, or challenge well-established conceptions in the general philosophy of science.” (p. 18). This is arguably the easiest chapter for those who have a background in philosophy (and are accordingly familiar with philosophy of science) but have little knowledge of linguistics; relevant aspects of the ideas of Thomas Kuhn, Karl Popper and Willard Van Orman Quine, notably, are discussed, and a section is devoted to the distinction between realism and antirealism.

Chapters 4 (“Case Study I: Infinite Generalisation in Linguistics”) and 5 (“Case Study II: Language Models and Linguistic Theory”) focus, as the titles indicate, on specific case studies. The first “[…] is meant to exemplify an issue in the philosophy of science concerning the use of powerful formal apparatus in describing and explaining natural [phenomena].” (p. 40), while the second “[…] can be read as a case study in the role of statistical, engineering models in science.” (p. 49). In this chapter, Nefdt discusses germane aspects of a notably timely topic, namely, Artificial Intelligence, and in particular large language models (LLMs). Chapter 6, “The Philosophy of Linguistic Subfields and Future Prospects”, considers how the philosophy of linguistics might develop.

Having outlined the contents, they may now be evaluated by answering the question of whether the two challenges mentioned above are met, so whether the book is accessible and covers relevant topics.

As for the matter of accessibility, it is important to observe that those who only have a background in philosophy – and accordingly not have a background in linguistics as well – may be expected to be sufficiently familiar with semantics (or at least formal semantics) and pragmatics to be considered intended readers of this book, but they cannot be presumed to have specific (or even basic) knowledge of other subfields of linguistics. Such readers may have difficulty readily grasping some of the details that are presented, and being able to (properly) evaluate them of course requires even greater acquaintance with linguistics. That said, Nefdt admittedly does provide explanations, making an effort to clarify what is said to the uninitiated reader. Some issues, conversely, require basic knowledge of philosophy, in particular philosophy of science. So the ideal reader would have a background in both linguistics and philosophy.

This is no surprising observation, perhaps, given the title of the book. Still, while it would not, in line with what was just remarked, be recommended to those who are not acquainted with linguistical issues, a lack of acquaintance with philosophical issues should not present difficulties in appreciating what the book has to offer. Linguists do not need to read the book in order to gain new insights into specific research results, but this observation is not tantamount to a negative assessment, since it is not the author’s goal to present such results here, but rather to reflect on linguistics itself. From that ‘metalinguistic’ perspective, the author takes them on a tour through linguistics, and in particular syntactic and semantic matters, while also considering the (nature of) the discipline as such.

The topic of the purview of philosophers has been explicitly addressed elsewhere, in a (written) debate with Herman Cappelen. Cappelen maintains: “In order to understand natural language semantics you need the kind of training that linguists get. You need training in phonology, syntax, semantics, pragmatics, and forms of morphology, and all the other topics that you get a training in when you do a graduate program in linguistics. Philosophers don’t spend their time being trained in this way and so it’s an unwise use of academic resources to have philosophers work on these issues.” (Cappelen 2017, 748; cf. 744). Cappelen’s observation, which he takes to amount to the position that philosophers not only cannot but should not engage in research in linguistics, only pertains to subdomains of theoretical linguistics; if other domains, such as applied linguistics, are also considered, an even greater the challenge – for philosophers – is at issue.

Still, Nefdt apparently does not consider what Cappelen advances problematic. He rightly observes that “[…] philosophers seem to be placed in precisely the right position to do work in formal semantics, training-wise at least.” (Nefdt 2019, 246; cf. 250: “Formal semantic analysis is part of philosophy whether we like it or not”). Importantly, however, as Nefdt grants (Nefdt 2019, 246), the methodology of formal semantics differs significantly from the methodology of syntax, phonology and morphology. Departing from an (exclusively) philosophical position is a prerequisite for understanding theories presented in these fields, and in particular for being able to produce valuable research oneself. Insofar, then, as other fields than semantics and pragmatics are concerned, if what philosophy of linguistics has to offer is to be properly appreciated those who only have a background in philosophy do not seem to constitute the ideal readership, in line with was remarked above.

As for the matter of the topics that are discussed, given the title of the book one expects the domain of linguistics to be covered, so not just theoretical linguistics. After all, if the scope were to be limited to the latter domain, the title ‘The Philosophy of Theoretical Linguistics’ would have been more apt. Strikingly, this is precisely the title of a book that the author produced a year before (Nefdt 2024). While that book, judging by its title, would (potentially) deal with fewer topics than the one under discussion, it includes an entire chapter that is concentrated on pragmatics. Conversely, The Philosophy of Linguistics would be expected (in principle) to deal with the entire field of linguistics, or at least to have a wider scope than the former book.

That is not the case, however. In fact, applied linguistics is mentioned only once, when Nefdt observes: “Applied linguistics is perhaps a philosophical blind spot. This might be because theoretical linguistics itself often made little impact outside of purely theoretical contexts.” (p. 57). Psycholinguistics and neurolinguistics are touched upon; neurolinguistics appears to be qualified as a subdomain of theoretical linguistics (p. 58), and psycholinguistics is explicitly characterized as such (p. 57), while they may, conversely, be said to be separate fields of research or at least multidisciplinary research domains. What is considered part of (theoretical) linguistics is of course a minor issue; the reason to point to Nefdt’s demarcations is that they make it clear what the answer to the question of what topics are discussed could be.

The choice to focus on theoretical linguistics (and, even if ‘theoretical linguistics’ is taken so broadly as Nefdt does, to devote little attention to other domains than those to which it is usually taken to be limited (i.e., as mentioned, syntax, semantics, phonology and morphology)) might be deemed justified on account of the fact that the book is too short to offer sufficient room for an extended scope, but the author need not of course have observed this limit and could, in other words, have written a longer book.

The author has produced a concise book in the form of an overview, discussing various topics rather than arguing why a specific theory is correct, the fact that he at times does take a stance and frequently refers to previous publications of his own in which he does defend a theory notwithstanding. A benefit of the shortness of the work is that readers can gain the insights that are offered in little time, but it does mean that in-depth analyses, such as those which the author himself presents in other work (for example (again), Nefdt 2024), are not possible, adding to the challenges already mentioned for those who are not specialists with respect to the topics that are discussed. The study is, in line with the author’s design for the book (p. 55), not completed by a conclusion (unless chapter 6 is considered a substitute, in line with the author’s own observation), but given its nature as – again – an overview this is not a deficiency.