Interview with Sasha Bergstrom-Katz and Tomas Percival, co-editors of the April 2025 `Special Issue ‘The material force of categories’.
HHS: Could I just start by asking you to introduce the special issue – what interested you about the ‘material force’ of categories?
Sasha: The Special Issue emerged out of a common set of interests about how categories have the capacity to materially move people around. We were both working on projects related to this: I was working on a project on intelligence testing and Tomas was working on digital prison assessments and modes of categorization in prisons in England and Wales. And we wanted to think together about this issue, connecting stories of the production of forceful categories from different, yet interconnected fields and institutions. So we put together a symposium to bring some of our mutual interests together. There was a panel on intelligence testing, one on digital culture, and one on mental health diagnosis. This is where this idea for the Special Issue came from. Some of the interests shifted through the panels, as well as through the editorial process. We came to think a little bit more about how the categories themselves are made, and how plastic these categories can be, as we talk about in the introduction. The interest shifted from focusing just on materiality because we really saw how malleable these categories were in all the cases that we were pulling together.
Tomas: We were interested both in how categories emerged from formal and informal processes—such as modes of practices of assessment—and then how those categories enacted forms of institutional decision-making that, as Sasha said, move people. In the prison system, for example, categories of so-called risk can inform determinations of which kind of security level you are subject to. Additionally, it became interesting to ask not only how assessment processes categorize but also how those processes transform the category in the process of the making of the category. How do the different institutions in which one ends up moving through based on what category you’re assessed, change the category too? What forms of resistance, friction and feedback enacted in relationship to the ways in which categories place people in particular contexts?
HHS: In your Introduction you discuss the plasticity of categories – could you explain what you mean by ‘the productive power of plasticity’ and how this differs from accounts of categorization that emphasise things like restraint or reduction?
Tomas: This is one of the things that really emerged from the various conversations we had with the people during the symposium. When we heard people’s examples we noticed that in each case they were moving beyond the well-rehearsed discourse around categories as being reductive. In these examples, when we investigate how they’re actually operationalized with the decision-making processes, it’s inversely their capaciousness, their ability to capture a wide variety of things or to have fluid boundaries that allow for them to be institutionally productive. So for us, this plasticity of the categories became a useful site of critical analysis in order to understand how they operate in practice.
HHS: Would you be able to identify some common threads and themes that link the articles in the special issue?
Tomas: There’s a series of throughlines that connect variously with the different articles. One is clearly mental health and how a question of the diagnostic is mobilized in order to determine mental health, and that ranges from Alfie’s article in relationship to the difference between a UK and US diagnosis of schizophrenia to Eoin’s work on mental health Chatbots or Becka’s in terms of how personality disorder got transformed in the prison system. Across all of these is the question of the plasticity of the diagnostic category and how the diagnosis is constructed. A second theme might be something like digital culture, and how technical modes of recording, processing, storing and transmitting data affect determinations of categories. Thirdly, there is a theme of containment and how various practices of categorisation enact modes of containment and filtering across various institutions. It was interesting to try and write the Introduction because there were numerous ways we could categorize these categories. Instead, we tried to find more non-figurative accounts of them rather than grouping them by, say, mental health because we wanted to trace the material force of these categories across the different spheres.
HHS: Could you describe how Margarita Aragon’s article ‘Subjects to be dealt with’: Disability, class and carceral power in early 20th century Britain’ conceptualizes categorization?
Sasha: One of the things that drew me to Margarita Aragon’s work was that she concentrates on the Mental Deficiency Act and the determinations of ‘subjects to be dealt with’. This is a phrase that comes out of the handbook Mental Deficiency Practice (1932) and in the Mental Deficiency Act. But in a sense, it’s not a category that the handbook defines. It’s a phrase that, in some ways, points to what might otherwise be called deficiency, idiocy and so-called defectives, but she concentrates on this category of ‘subjects to be dealt with’ instead. This is a really useful way of actually getting a fundamental question of what the Mental Deficiency Act was meant to do. It was meant to identify the ‘subjects’ whom the state wants or feels it needs to ‘deal with’. Feeble-mindedness isn’t, for example, a category that can be collapsed into ‘subject to be dealt with’ because there are other conditions that need to be fulfilled to be a subject of the MDA. When Margarita provides examples from the Handbook, she describes people who might be similarly determined to be, in the language of the text, defectives or feeble-minded, but it’s actually some of their material conditions, personal histories, access to wealth, etc. – that determines their ‘subjectness’ under this act.
HHS: Julian Molina’s article ‘examines the entanglement of British criminology and undercover policing (‘Spycops’) in the UK government’s response to racism in 1981’ – how does it contribute to understandings of racial categories?
Tomas: Julian’s is an interesting article to think about categories with because he’s pushing back in some way against the categories of the human sciences. Instead, he conceptualizes it as a kind of category of action, to emphasize how these categories emerge from and interact with this law-and-order information infrastructure. His article addresses a moment in the early 1980s when there was public outrage and contestation over racist attacks and a lack of what’s perceived to be—and no doubt was—a lack of police response to those racist attacks. He examines how once this kind of public demand is placed upon the police and the Home Office a whole set of criminological knowledge is produced in its wake. But, and this is the key for us, in the process of the production of this knowledge the object of analysis and attention shifts. So it goes from being a narrow information-gathering practice around these racist attacks, and instead starts to also incorporate other things like anti-racist organizations. All these various other kinds of movements which have been campaigning against these racist attacks by the National Front, then become incorporated into the information infrastructure, such that they then can become the subject of police activity as much as the racist attacks themselves.
HHS: Becka Hudson’s article ‘Material pathologies’ examines the category of ‘personality disorder’ in the context of the British prison estate – she claims this category is ‘broad and malleable’ – what are the material effects of that? What does she mean when she argues that the diagnosis ‘did things’?
Sasha: Becka’s article focuses on how prisons have held on to the diagnostic category of personality disorder, which, outside the prison system is no longer a popular mental health diagnosis. I think one of the reasons that it does this is because it’s such a malleable category, so it is capacious, as Becka calls it, and thus opens up for very many people to be diagnosed with it. She describes that individuals often find identifying with this diagnosis useful, yet it is also used in the prison as a predictive category. There’s an institutional attachment to this category because of the slipperiness of it.
Tomas: Part of her research was looking at parole board decision-making in relationship to personality disorder. When someone’s case is in front of the parole board, they have to demonstrate how they have reduced the risk asked of them, essentially to demonstrate rehabilitation. One of the interesting things for me was how, in parole board decisions around personality disorder, someone could be understood to have fulfilled
the requirements set out for them too well. This can be read as disingenuous and is then pathologized as being part of their personality disorder. The idea that you might have self-reformed too well can then be seen as again reflecting back on this category. And importantly, it is unlikely that the people making these determinations are trained in mental health, so these are also non-professional judgments around personality disorder that are also having such effects.
HHS: In ‘How does a mental health chatbot work?’ Eoin Fullam examines the chatbot ReMind – what is the significance of including an article on this technological form of categorization as part of the Special Issue?
Tomas: We included Eoin’s project because it highlights a contemporary example of how mental health is categorized through technical practices. For us, what was most interesting about Eoin’s article is how categories that preexist the chatbot, drawn from the psy-disciplines, become formatted into a technical logic of tagging. An algorithm is used in a specifically demarcated and limited way within the app such that a conversation with the user becomes a set of tags, and then those tags are mobilized in a decision tree in which categories are parroted back to the user. It’s not a process of diagnosis, but one in which the user articulates a concern and the app provides a set of options back in the form of self-help, or Mindfulness or CBT courses it has on offer. There’s this interesting way in which it’s explicitly not diagnostic. Still, it mirrors diagnostic categories and forms of treatment in relationship to those diagnostic categories that it has available to it.
HHS: Alfred Freeborn (Max Planck Institute for the History of Science) was awarded the 2024 History of the Human Sciences Early Career Prize for his essay ‘Testing Psychiatrists to Diagnose Schizophrenia: Crisis, Consensus and Computers in post-war Psychiatry’. How does he understand diagnosis as a form of categorization?
Sasha: Alfred’s case study focuses on a particularly fascinating case in the history of schizophrenia research wherein a cross-continental project between the US and the UK attempts to pin down schizophrenia through its diagnostic methods. In this case study, his protagonists are not focused on defining schizophrenia, but instead on being able to ensure that diagnostic criteria can be agreed upon and shared. He makes clear that their project was not about validation or even regulation, per se, but being able to standardize the diagnosis processes. He also talks about the various forces that made such a project necessary—for example, insurance and other kinds of bodies which would require a more standardized approach to diagnosis. It is another rich example of shapeshifting of categories that, again, don’t necessarily reflect so much about what schizophrenia is but how the category is shaped and the external factors that shape it.
Additionally, related to some of the other articles in the Special Issue, the use of modern technologies is quite interesting here. These psychiatric professionals took up emerging technologies such as computational analysis and videotape as medical tools, which then brings us to question the professional knowledge of the psychiatrist and what is transformed through a more standardized, and even mechanized, procedure.
HHS: What do you hope that people take from this special issue that could help them to think through this ‘shapeshifting’ aspect of categorization?
Sasha: The example of schizophrenia is a useful one because instead of just thinking about the genealogy of a category we can think about how it’s constantly being made and remade. This shapeshifting and plasticity is not about the progression of the making of categories but about messiness and contingency.
Tomas: It’s an attempt to pay particular kinds of attention to how categories operate in practice. Meaning not how they’re expected to operate. Instead, once you get into the nitty-gritty of all of the examples we have in the Special Issue we start to see that categories do much stranger, more contingent, and often harmful things differently than what we might expect when we think of the category in the abstract. That’s what we have tried to emphasize with our Introduction and most of the authors have paid attention to that in their own work. Across the articles, there’s methodological attention paid to the question of what happens when categories operate.
Interview conducted by Hannah Proctor. The interview was edited for length and clarity.
