Kevin Matthew Jones’s volume Psychological Classification and Diagnosis in Asylum Statistics places at the forefront a topic which is oft-discussed, but rarely examined in exhaustive detail: the categorisation of mental disorders in its broader contexts, from bureaucratic knowledge-making to political and professional structures. The book examines the historical development of psychological classification in Britain through the lens of asylum administration and mental health statistics in a longue durée perspective, between the early 1800s, marked by the publication of French alienist Philippe Pinel’s nosology, and 1948, the launch of the NHS in Britain, which redefined public health governance. Its central object, the choice of which helps to narrow and focus the layered and entangled history of nosologies and nomenclatures, is the Table of the Forms of Insanity, a list of diagnostic categories introduced in the wake of the 1845 Lunacy Acts and used – albeit with repeated revisions – until its replacement by the International Classification of Diseases after the Second World War. Following in the footsteps of, among others, Ian Hacking, Volker Hess, and Andrew J. Mendelsohn, rather than treating diagnosis as a product of clinical theory alone, the book approaches the bureaucratic, legal, and statistical frameworks as structures that not only represented and inscribed psychological knowledge into pre-set forms but also operated as technologies that co-produced this knowledge and therefore determined asylum practice and public health governance.

The volume foregrounds this argument thoroughly in the introduction (Chapter 1), treating it as a common thread that keeps together the further discussion of the theoretically dense and complex history of the development of psychological diagnosis within public health administrative systems that required diagnoses to be recorded, standardised, and reported in order to maximize efficacy. Embedded in a carefully contextualised narrative, the author shows the process through which, from the mid-nineteenth century onward, asylum medical officers became legally obliged to assign diagnostic labels at admission and return these data to central authorities within constantly changing mental health care infrastructures and jurisdictions. These requirements, marking the beginning of large-scale mental health data collection, in turn, created pressures to standardise diagnostic terminology. The Table of the Forms emerged as a practical solution to these pressures, functioning primarily as a tool for record-keeping and statistical aggregation rather than as a theoretically rigorous nosology. Nonetheless, it became the closest approximation to a national standard for psychiatric diagnosis in Britain during the Victorian and early twentieth-century asylum era.

The early chapters trace the intellectual and institutional origins of the Table. The diagnostic categories recommended by the Lunacy Commission in its first report drew heavily on Philippe Pinel’s symptom-based and concise division of insanity into mania, melancholia, dementia, and idiocy. Jones, based on careful philological reconstruction, argues compellingly that these categories were, on the one hand, built on British antecedents such as William Cullen and Thomas Arnold’s classifications, and, on the other hand, were transmitted to Britain through figures such as James Cowles Prichard, a Lunacy Commissioner himself, who adapted the newly minted French concepts to British medical sensibilities and emphasized their practical utility. Although Pinel’s system attracted criticism and continued to do so for the rest of the nineteenth century for its lack of etiological grounding, its reliance on observable symptoms made it particularly suited to asylum administration at a time when specialised psychiatric training was limited. Consequently, these categories became embedded in asylum paperwork and statistical returns, acquiring durability through institutional use rather than scientific consensus.

The first part of the book (Chapters 2–4) focuses on the expansion of a system, in which the formalisation of the diagnostic practice created new epistemic expectations. Paper technologies not only represented but co-produced psychiatric knowledge, and the asylum data thus generated were increasingly seen as a potential resource for understanding the prevalence, causes, and course of mental disorder. However, the diversity of diagnostic practices and terminologies across institutions soon exposed the limitations of existing classifications, and from the 1860s onward, debates over the standardisation of diagnostic categories intensified. Critics of the symptom-based Pinelian system – most notably David Skae and his supporters – argued for classifications grounded in aetiology and the natural history of disease. In their view, physiological and materialist approaches promised greater scientific rigor and more reliable distinctions between disorders. However, as the book argues, they also posed practical problems for asylum statistics, as causal diagnoses were often speculative and difficult to apply consistently. The prolonged debates leading up to the 1882 revisions of the Table reveal a fundamental tension between scientific ambition and administrative feasibility, while the eventual outcome shows a compromise: the retention of traditional symptom-based categories, supplemented – but not replaced – by aetiological considerations.

The second part of the book (Chapters 5–8) concentrates on the first half of the twentieth century in the context of broader administrative and scientific transformation and the destabilisation of the symptomological approach in psychiatry. By reconstructing the transnational circulation of ideas in medical theory, Jones convincingly explains that the focus of classificatory debates shifted again at the turn of the century, particularly with the growing influence of Emil Kraepelin’s work overturning older diagnostic categories and coining new ones. Examined from the broader perspective of public health history, the book argues that the overcrowding of asylums and the declining discharge rates added to the pressure of numbers in institutional psychiatry, while therapeutic pessimism took hold, and prognosis became an increasingly important concern for the planning of admission, placement, and care within the healthcare system. In this context, the Kraepelinian classification, which emphasised the course and outcome of mental disorders, appeared to offer a solution by linking diagnosis to prediction. The 1907 revisions to the Table reflected this shift, introducing concepts aligned with Kraepelinian psychiatry while retaining familiar terminology. At the same time, these revisions coincided with reforms to asylum record-keeping, including standardised medical registers designed to streamline data collection and enhance statistical reliability.

While discussing these processes related to the narrower issue of classification could at first glance seem somewhat detached from social and political processes, the final chapters succeed in highlighting that these classificatory changes were embedded in broader non-medical contexts. As asylum statistics circulated beyond medical circles, they informed public debates about degeneration, heredity, and the perceived increase of insanity, while eugenic ideas gained prominence in discussions of mental health data, particularly after the passage of the 1913 Mental Deficiency Act, which reclassified large segments of the institutionalised population. At the same time, as a consequence of administrative reshuffling, interest in detailed diagnostic statistics waned under the Board of Control, and the publication of national data on forms of mental disorder became increasingly sporadic.

The final chapters address the last major attempt to reform the Table in 1934 and the emergence and introduction of a new system. By the interwar period, with the pluralisation of scientific approaches and theories, British psychiatry was marked by competing and often incompatible frameworks, including hereditarian theories, somatic psychiatry, psychoanalysis, and emerging social approaches to mental illness. In response to these transformations, the revisions committee sought to accommodate these divergent perspectives within a single classificatory system, merging symptomological, etiological, and psychological elements. However, the result was widely criticised as incoherent and impractical, and the failure of the 1934 revisions underscored the limits of national classification efforts rooted in asylum administration at a time when psychiatry was becoming increasingly international and integrated into general medicine. The book concludes by tracing the displacement of the Table during the reforms of the 1940s. The planning of a national health service and the adoption of the Royal College of Physicians’ nomenclature paved the way for the incorporation of mental disorders into the International Classification of Diseases in 1948, and in this context, the Table of the Forms appears as a historically specific ‘artifact’: a classificatory system shaped by the needs of asylum governance and statistical oversight, whose decline reflects both structural changes in health administration and shifting conceptions of mental disorder.

In sum, Kevin Matthew Jones’s volume on the evolution and transformation of psychological classification in Britain and its ties to the ever-changing structures of public health administration and asylum governance, as well as the changing perception of mental illnesses, is well embedded in an emergent approach to knowledge-making in the psy-sciences in relation to their bureaucratic contexts. While the chapters are well-focused and formulate clear theses, never losing sight of the central idea of the book outlined in the introduction, on occasion, the argumentation gets somewhat repetitive and circular, while the tables and figures included in the volume could have yielded more elucidation. Additionally, the sole focus on Britain, with some references to France, but almost completely dismissing other bureaucratic cultures and their ties to psychiatric knowledge-making, makes the volume somewhat disengaged from European developments, even though the book examines structures and technologies that profoundly transformed nineteenth- and early twentieth-century European medicine. Despite these critical remarks, however, I believe that Kevin Matthew Jones’s timely choice of topic and the careful and reasonable handling of the source material, as well as the clear and logical structure of the book, which facilitates coherence and solid argumentation make the volume a fundamental read for those interested in medical epistemology, the psy-sciences, and their entangled bureaucratic contexts in the co-producing of knowledge and shaping medical practice – both in Britain and beyond.