Thinking in,with,across,and beyond cases with John Forrester

Abstract

We consider the influence that John Forrester’s work has had on thinking in, with, and from cases in multiple disciplines. Forrester’s essay ‘If p, Then What? Thinking in Cases’ was published in History of the Human Sciences in 1996 and transformed understandings of what a case was, and how case-based thinking worked in numerous human sciences (including, centrally, psychoanalysis). Forrester’s collection of essays Thinking in Cases was published posthumously, after his untimely death in 2015, and is the inspiration for the special issue we introduce. This comprises new research from authors working in and across the history of science and medicine, gender and sexuality studies, philosophy of science, semiotics, film studies, literary studies and comparative literature, psychoanalytic studies, medical humanities, and sociology. This research addresses what it means to reason in cases in particular temporal, spatial, or genre-focused contexts; introduces new figures (e.g. Eugène Azam, C. S. Peirce, Michael Balint) into lineages of case-based reasoning; emphasizes the unfinished and unfinishable character of some case reading and autobiographical accounts; and shows the frequency with which certain kinds of reasoning attempted with cases fail (often in instructive ways). The special issue opens up new directions for thinking and working with cases and case-based reasoning in the humanities and human sciences.

This special issue is a celebration of the work of John Forrester, who died five years ago in November 2015 and whose writings continue to inspire and provoke scholars across and well beyond the human sciences. In the aftermath of Forrester’s untimely death, much has already been written and spoken in appreciation, memorializing his many contributions, both to many disciplines and via his influence, pedagogically, on multiple scholars. Key here were the memorial events at the Department of History and Philosophy of Science at Cambridge (2016) and a colloquium at the École des Hautes Études en Sciences Sociales in Paris (2017). ¹ The Freud Museum London held two conferences, marking the posthumous publications of Forrester’s essay collection Thinking in Cases (Forrester, 2017) and his important work Freud in Cambridge, co-written with Laura Cameron (Forrester and Cameron, 2017). ² Psychoanalysis and History, the journal that Forrester edited for over a decade, produced a special issue in 2017. In the words of the guest editors, Matt ffytche and Andreas Mayer, the special issue was ‘couched not as a memorial, but as a first step in developing serious scholarly work on John’s own many projects – which in many ways remain ongoing endeavours’ (ffytche and Mayer, 2017). ³ The present special issue seeks to continue in that vein: authors follow the multiple intellectual threads that make up Forrester’s Thinking in Cases collection. They turn these threads in the light and weave them in new configurations; they establish new relationships between figures who might be considered to reason with cases; they take Forrester’s insights to places he did not explicitly consider himself (e.g. the case history in the colonial context, or the logic governing current discussions of transgender equality). In so doing, they open up new perspectives on the intertwined histories of psychiatry, psychology, medicine, philosophy, governance, and jurisprudence. The issue also revisits and celebrates the enduring contributions of the first article that gives the collection its title: ‘If p, Then What? Thinking in Cases’. This was originally published in History of the Human Sciences in 1996 (Forrester, 1996), and its arguments have reverberated through and beyond the journal in the near quarter of a century since.

Cases – as a way of thinking about experience – remain central to the human sciences, the medical humanities, and beyond. With characteristic verve and erudition, Forrester in ‘If p, Then What?’ begins with the psychoanalytic case, which is, he speculates, ‘a new form of accounting for the self in 20th-century scientific and popular discourses’ (Forrester, 1996: 13). In a restless and insistent passage, he pushes this idea further, asking about the genealogy of the case itself, which he supposes would take in the contributions of Michel Foucault (on the dossier) and Carlo Ginzburg (on forensic medicine and art history). But Forrester is unsatisfied with this and asks, ‘Is not there an autonomous history of the medical case-history? Is not the history the distinctive feature of Hippocratic medicine itself?’ (ibid.). By the end of the essay, Forrester has allowed the reader to understand how much is at stake in his overarching question: ‘What are the specific modalities – historical, epistemological, political – by which reasoning in cases…has been embedded in disciplines and practices…?’ (ibid.: 21). It is this kind of pushing through or zooming out, the drive to further interrogate and complicate common-sense categories, linear histories, and disciplines whose histories and styles of thought have too frequently been kept conceptually distinct from one another, that we have tried to capture and nurture in this special issue.

Following citations of ‘If p, Then What?’ in History of the Human Sciences alone demonstrates how Forrester’s article has shaped thinking not only on ‘the case’ but on epistemology, the archive, sexuality, and beyond (e.g. see Chiang, 2010; Lemov, 2018; Osborne, 1999; Reed, 2001; Savoia, 2010; Sealey, 2011). Indeed, we might read Forrester’s 25-page essay as one of the cornerstones both of this journal, and of the constitution and conceptualization of its object of investigation – the history of the human sciences – more broadly. For Forrester’s work, as Andreas Mayer has emphasized, reoriented how we might think of the history of psychoanalysis ‘within a new subfield that slowly emerged in the 1980s and 1990s: the history of the human sciences’ (Mayer, 2017: 157). To pick up a thematic that is at work throughout the special issue, Forrester’s 1996 essay has itself become a kind of ‘exemplary’ case on how to investigate, think through, and write about the case. If it has subsequently helped inspire the production of other ‘cases’ that might fall within a series (e.g. Furth, 2009; Morgan, 2012 – and the essays we collect here), it also invites the reader to reflect on whether and how each contribution to the special issue thinks and writes with, from, and beyond Forrester’s 1996 case.

The idea for this special issue of History of the Human Sciences emerged when one of us (CM, at that point the journal’s book reviews editor) initiated plans for a ‘review symposium’ on Thinking in Cases. The level of interest that emerged from tentative early requests for contributions convinced both of us that we needed a more capacious vehicle for people’s reflections. And so we invited contributions from those whose work ‘bears in some way upon the work John started with “Thinking in Cases”’, welcoming those who ‘would like to contribute to such a dialogue with John’s work, and with each other’ (‘Thinking in Cases’, 2017). We were anticipating at that point contributions of 3000 words. But that turned out not to be enough. Some offered full papers, and so we invited authors to offer essays of varying lengths. We deliberately did not try formally to standardize the submissions in length or in terms of the manner in which authors engaged with Forrester’s book Thinking in Cases as the contributions passed through peer review. It is a testament to the quality and fecundity of Forrester’s work – of its ability both to analyse and to encourage the proliferation of networks of knowledge – that this transformation in scale happened almost entirely under the weight of the enthusiasm contributors had for developing his ideas. The issue includes contributions from authors working in and across the history of science and medicine, gender and sexuality studies, philosophy of science, semiotics, film studies, literary studies and comparative literature, psychoanalytic studies, medical humanities, and sociology.

Julie Walsh’s article, ‘Confusing Cases: Forrester, Stoller, Agnes, Woman’ (Walsh, 2020), argues that there is a ‘structural affinity’ or ‘formal alliance’ between issues of gendered identity and the methodological questions raised by the psychoanalytic case study. Walsh show us how the psychoanalytic case is based around ideas of development and becoming: of negotiation, performance, interruption, and subversion. Using Forrester’s analysis of Robert Stoller’s case of Agnes (whose gender identity is complicated and revealing), Walsh draws out a fundamental characteristic of case-thinking: ‘To think in cases is to practise those lines of movement – the transitions, transferences, and interruptions – that characterize the non-linear temporalities of becoming’ (ibid.: 29). This flexibility, the fluidity that a psychoanalytic case demands, is expanded through close engagement with a group of feminists influenced by psychoanalysis (including Simone de Beauvoir, Juliet Mitchell, Judith Butler, and Denise Riley), who focus on how woman is a category marked by negotiation, performance, interruption. Psychoanalytic case logic shows how womanhood is mutable, provisional, and achieved in context – rather than relying on any essence or ideal. The article revivifies Forrester’s insistence, across his oeuvre, that the psychoanalytic case study raises a ‘fundamental ambiguity regarding who or what is being framed as the case’ (ibid.: 20; emphasis in original): such an argument, Walsh makes clear, has much to contribute to contemporary debates around the nature of sex and gender identity.

Matt ffytche’s contribution demonstrates, like Walsh’s, how profoundly psychoanalysis disrupts conventional ways of narrating a life. But ffytche does so through attending to cases very different from that of Agnes – those in which investigators are also the subjects and the writers of their own cases. In ‘Throwing the Case Open: The Impossible Subject of Luisa Passerini’s Autobiography of a Generation’, ffytche (2020) brings together a group of texts that constitute ‘new kinds of autobiographical work…with radical, experimental, or critical dimensions, which end up dismantling the boundaries of the conventional life, and the conventional case, without necessarily putting anything solid in its place’ (ibid.: 35). This novel self-narration troubles the self-evidence of ‘the case’ by stressing how subjectivity and selfhood are indeterminate, unfinished, and flexible. The illusion – and the utility – of the case is that it isolates and analyses an individual. The texts that ffytche analyses include, alongside Passerini’s text, those by Walter Benjamin, H. D., Frantz Fanon, Wilfred Bion, and Eve Kosofsky Sedgwick; they refuse in their different ways this illusion of a completed or closed self, and trouble what is commonly thought to be the boundary a case delineates between and individual (inside the case) and their ‘context’ (outside the case). Instead, these accounts involve ‘large swathes of structural indeterminacy…[dominated] by free associative leaps of their authors, and by tones of hesitancy, loss, crisis, or rapture’ (ibid.: 36). Crucially, these texts are methodologically innovative and structurally unorthodox. Because when thinking with cases, as ffytche argues, ‘it’s not enough to tell the history of cases, because these, confined within their professional limits, are always outstripped by the changing versions of “being a subject” they are trying to map’ (ibid.: 44). ffytche echoes Forrester in the latter’s framing of the lure of psychoanalysis as ‘the singular life as the test-case’ (Forrester, 1996: 21) – but such a test is, in ffytche’s article, persistently exploded. It is not able to be ‘“nailed down” to the level of the individual’, as Forrester contends in his essay on Kuhn (Forrester, 2017: 49).

Shaul Bar-Haim’s article represents a moving continuation of a conversation with the man as well as the author named John Forrester, returning to a moment, a decade before, in which Bar-Haim, in predoctoral days, met Forrester. Forrester, in a pedagogical utterance that would find its force belatedly – in the gift of the essay that Bar-Haim gives to us, the readers – suggested, in relation to Bar-Haim’s proposed research ideas, that ‘all…was already done’. All, that is, aside from an investigation of Michael Balint. In ‘Proving Nothing and Illustrating Much: The Case of Michael Balint’, Bar Haim (2020) thereby answers Forrester’s provocation by focusing not only on what it might mean to ‘think in cases’ but also on whom we may not yet have noticed as a ‘thinker in cases’. With reference to Forrester’s own work on Balint, some of it unpublished and unfinished, Bar-Haim contends that the Hungarian psychoanalyst Balint is for Forrester – and also for us – an exemplar in his ability to connect historical and philosophical case-based reasoning, on the one hand, and clinical reasoning, on the other. The article takes us through some of Balint’s later work with patients, and how this provoked him to reflect in a self-conscious way upon the doctor’s role in psychological illness. The doctor cannot just seek to manage and heal dysfunctional family dynamics, because they are so often a participant in the drama. Using what Balint called the ‘apostolic function’, doctors provide an example to families of what ‘tenderness’ or ‘affection’ looks like. This then circles back to the point of any case in the first place: to serve as an example – or, as Balint would have it, an ‘illustration’.

The special issue then turns from one exemplary individual to another, as Rachel Weitzenkorn’s article focuses on American psychoanalyst René Spitz. In ‘Boundaries of Reasoning in Cases: The Visual Psychoanalysis of René Spitz’, Weitzenkorn (2020) directs our attention to visual records of cases, specifically the films that Spitz and colleagues made to showcase and analyse the distress of institutionalized infants. Whilst Spitz ‘claimed that the mechanical gaze of the camera enabled generalizable and standardized observations, rather than the specific story a case might tell’ (ibid.: 78), Weitzenkorn’s analysis brings out how the choices of shot, and the use of close-ups for emphasis, show how ‘the choice of the creator to focus on this and not that is revealed. Spitz’s films reveal their own construction’ (ibid.). Thus the attempt to produce generalizable, objective evidence is unmasked: Spitz’s project is, ultimately, a failure. This loops back around to Forrester’s focus on the failures of cases: specifically, what this might tell us about subjectivity and attempts to capture it. In the same way that a case reveals much more (and much less) than simply an individual life, but also fails to produce objective, generalizable knowledge, these films bring into sharp relief the central problems contained within case-based reasoning. Cases show individuals whilst also promoting them as uncertain exemplars. Just as Forrester disrupts any clear separation between cases as deployed in medicine and those found in law and casuistry, Weitzenkorn disturbs the historian’s too easy separation between psychoanalysis and experimental psychology. She pushes the boundaries of case-reasoning by showing that outside the consulting-room, outside of the written word, the central problem remains: what is it that a case shows? The supposed self-evidence of the visual is no way out.

Like Weitzenkorn, Erik Linstrum explores the logic of the case in a hybrid form – here examining the tensions between the bureaucratic ambitions of the colonial case and the case’s individualizing tendencies. Like Weitzenkorn, he also finds failure. In ‘The Case History in the Colonies’, Linstrum (2020) takes us from the space of the clinic to the logics of imperial governance. Knowledge is power, and histories of empire have long focused upon the weapons of categorization, aggregation, and abstraction – ways of knowing imperial subjects – alongside the more conventional weapons and enforcement that were essential to empire’s continued existence. However, the case-history investigations into so-called ‘primitive minds’ were full of wishes for revenge against the colonial masters, and unsurprisingly, ‘imperialists simply could not and did not acknowledge the depth of the psychic wounds inflicted by empire. What they emphasized, instead, was the idea that opposition to empire arose from mental disorder’ (ibid.: 90). Whilst this did enable the case history to function as an exemplar of native pathology, Linstrum argues that ‘even the constrained individuality of the case history ultimately proved too unruly for the taste of colonial rulers’ (ibid.). Ultimately, the individualized, detailed, trauma-filled case studies were unsuitable for the project of colonial governance, because they contained too much material that was multivalent and potentially subversive; empires cannot abide subversion for long. Linstrum brings out, in relation to settings very different from those of many of Forrester’s chosen cases, the subversive and anarchic qualities that inhere in cases, concluding that they were ‘less a form of useful knowledge for colonial rulers than a source of inconvenient truths’ (ibid.: 92).

In ‘Periodical Amnesia and Dédoublement in Case-Reasoning: Writing Psychological Cases in Late 19th-Century France’, Kim Hajek (2020) examines the kind of reasoning that animates psychoanalytical cases. This is achieved by taking us backwards from Freud: Hajek turns to Èugene Azam’s 1876 account of Félida X, whose double personality and periodical amnesia gave part of the context for the emergence of a new kind of psychological observation and analysis – a new way of ‘thinking in cases’. Hajek skilfully draws out another tension that becomes characteristic of cases, between ‘vertical’ and ‘horizontal’ reasoning. Vertical reasoning is classificatory and generalizing, tending to subsume the meaning of the individual in the overarching category, whereas horizontal reasoning seeks detailed and specific knowledge about the individual as a way to understand them. Notably, vertical reasoning removes both the patient and the observer from the scene. In the case of Félida X, there is a shift, Hajek shows, from the kind of vertical classificatory writing used to describe surgery and amputation to the involved individuality of periodical amnesia and double personality: ‘Under the challenges of representing psychological phenomena, the depersonalized medical style gives way to a narrative richness’ (ibid.: 105). In this way, Hajek installs Azam in a series of thinkers in cases who, chronologically prior to Pierre Janet, Sigmund Freud, or René Spitz, insert themselves into the case as figures who observe and narrate. For Hajek, the ways that cases are written – something that Félida X’s case makes clear in its switching between vertical and horizontal styles – are central to the kinds of reasoning they contain and allow.

Maria Böhmer’s article, ‘The Case as a Travelling Genre’ (Böhmer, 2020), brings into focus a further aspect of case-thinking, or more precisely another possibility that is unlocked when a case is written. This is the possibility of extensive travel. As Böhmer rightly points out, a key characteristic of the case is its ability to circulate in social networks. More than this, a medical case is written in a form that allows it to travel not only into different geographical contexts – and be understood as useful – but also to move transdisciplinarily: ‘Medical cases seem to travel easily beyond the context of medical science into the realm of popular literature and journalism’ (ibid.: 112). Thus the case as a unit of enquiry is mobile in multiple ways, and this is explored through the case of Mattio Lovat, a Venetian shoemaker who attempted to crucify himself in 1805. The rich and ambiguous (even vague) nature of this case prompted physicians specializing in mental diseases to speculate on the psychological aspects, whilst theologians looked at the possibly defective quality of Lovat’s childhood religious instruction. This all prompts us to analyse what enables cases to travel and to ‘circulate in networks’. Many contributors to the special issue (e.g. ffytche, 2020; Morgan, 2020; Walsh, 2020) have emphasized the importance of the reader of the case in understanding how thinking in and with cases takes place. Böhmer draws our attention specifically to ‘readers and their contexts’ when examining how cases are able to travel across geographical distances and different intellectual disciplines, ‘but also across different epistemic and literary genres’ (Böhmer, 2020: 123). Cases involve styles of thought, but as Böhmer reminds us, they also have material components that govern how they are read, written, and edited, and how they are able to travel.

Jeremy Burman brings Forrester’s work on cases, and especially on Thomas Kuhn, together with an appreciation of the influence of experimental philosopher and biologist Jean Piaget. In ‘On Kuhn’s Case, and Piaget’s: A Critical Two-Sited Hauntology (or, On Impact Without Reference)’, Burman (2020) takes us on a journey, inserting Piaget in a chain of influence, from Forrester, to his work on Kuhn, and back through Piaget’s influence on Kuhn. Crucial in this account is the idea expressed by Forrester that Thomas Kuhn was an historian (as opposed to a philosopher) insofar as he (Kuhn) attempted ‘climbing into other people’s heads’ (ibid.: 130). Burman’s complex and archivally anchored account of what he calls ‘Forrester’s Kuhn-inspired and Piaget-haunted approach’ shows that a significant part of the architecture and logic of case-thinking should be attributed to Piaget (ibid.: 146). And Burman demonstrates this in ways that revisits some of Forrester’s own preoccupations:

1. Who is influencing whom and how – and what kind of evidence would one adduce to answer such a question (see Forrester, 1991)?

2. How does one best conceptualize and represent the ‘tangled but non-identical’ threads that cross the epistemological domains of history, philosophy, and psychoanalysis when thinking about cases (Burman, 2020: 130)?

3. How might thinking in cases constrain as well as open up thought?

If, for Burman, thinking in cases ‘constrains our analyses’, it also means that the sources of the insights that constitute ‘thinking in cases’ are obscured. This is something that Burman decisively rectifies here, bringing Piaget back to haunt Forrester’s work through Thomas Kuhn.

Jacy Young engages with John Forrester’s point, made right at the beginning of ‘If p, Then What?’, about the aversion of psychoanalytical thinking to statistical analysis and reasoning. In ‘Thinking in Multitudes: Questionnaires and Composite Cases in Early American Psychology’, Young (2020) explicitly interrogates her own earlier thinking on this question by pushing off from Forrester to ask about the specific styles of reasoning in American questionnaire research in the late 19th and early 20th centuries. These styles were statistical in part but also involved (aggregations of) individuals – and as Young points out, these composite forms of ‘scientific thinking were not simply fuzzy but potentially productive, offering liminal spaces within which to conceive of novel forms of disciplinary knowledge’ (ibid.: 161). Young draws near, here, to Böhmer’s productive tension between vertical and horizontal reasoning, but also to Weitzenkorn’s account of the failures of Spitz, and to Linstrum’s charting of the failure of the imperial case study. For Young’s analysis shows that despite much work, questionnaire-based psychological research was able to escape the tension between the individual and the statistical only as ‘a mark of failure rather than a badge of success’ (ibid.: 170). What Young shows, in an article that opens up the logics of natural historical thinking, and of composite and exemplary cases, is that analysing ‘psychology’s history with Forrester’s thinking in cases in mind illuminates the inherent tension of the discipline’s statistical approach to understanding individuals’ (ibid.: 171). The incommensurability of these aspects of human lives and psychological research has much to offer in analyses of failure – if, indeed, that is the right word for so productive and revealing a tension.

Michael Flexer – in a way that recalls Burman’s manoeuvre with Piaget – takes head-on the notion of ‘thinking in cases’ by augmenting Forrester’s tools with some borrowed from semiotician C. S. Peirce. Specifically, through treating the case as a ‘semiotic sign’, Flexer, in ‘If p ⁰, Then 1: The Impossibility of Thinking out Cases’ (Flexer, 2020), argues that the creative practice of ‘abduction’ has been lost from Forrester’s thinking in cases. Flexer corrects the ‘linearity in the development of the case’ (ibid.: 179) that he sees in Forrester: whilst Forrester powerfully engages with cases as ‘rich qualitative narratives’, by excising abduction he is not able adequately to attend to how the ‘genre conditions’ through which cases are constructed constrain how they are able to offer up new insights for thinking in cases (ibid.: 191). Flexer grafts onto case-thinking Pierce’s abductive method: namely, creatively analysing a surprising or anomalous fact by asking what would have to change in our general understanding of the world to make this anomaly a run-of-the-mill occurrence. Flexer uses the example of the early stages of what would become known as the AIDS pandemic of the 1980s in North America, where diagnosticians, constrained by case-thinking, were unable to grasp the nature of HIV/AIDS or even get a handle on the affected demographic groups effectively. Flexer charges ‘thinking in cases’ with ‘working only with the post-abductive altered timeline of the case, and…[with] treating this as an ever-steady, ever-simple line of progression’; if we use Peirce and lean into abduction, we may be able to draw out ‘disruptive reverberations’ and appreciate how what in the end becomes ‘a case’ is strafed with a provocative and useful temporal complexity (ibid.: 179). If we open ourselves up to what might be considered ‘wildly unlikely’ (that is, something out of step with our preconceived ideas), we can escape the way that case-reasoning constrains our hypotheses. As Flexer notes in conclusion, a case ‘is not the particular or the singular, but the singular overlaid with and translated by the universal principles for understanding these singularities’ (ibid.: 193). Cases exist as individual units only because they already exist within an interpretive environment that enables them to be separate. Flexer inserts Peirce into Forrester’s account of thinking in cases to help break open the self-evidence of the case in a new way and offer new tools for clinical pedagogy and practice.

Mary Morgan’s article closes the special issue by attending just as closely as Flexer’s to the syntactical and logical implications of the title of Forrester’s 1996 essay – though to philosophically and formally different ends. In ‘“If p? Then What?” Thinking Within, With, and From Cases’, Morgan (2020) breaks the title of Forrester’s 1996 essay in two and analyses a number of different possible interpretations of the terms ‘if p’ followed by ‘then what?’, depending on where the question mark(s) go (‘If p? Then What?’; ‘If p? Then What’; ‘If p, Then What’). In an article that ranges widely across disciplines as heterogeneous as psychiatry, anthropology, sociology, and mathematics, Morgan extends her earlier writing on case-based reasoning (e.g. Morgan, 2012, 2019) to elucidate the differences between reasoning in cases, reasoning within cases, reasoning with cases, and reasoning from cases. The aim is ‘to develop an account that fits not just reasoning within the case, but more significantly reasoning from the case and from its materials in ways that prompt various kinds of legitimate knowledge beyond the case itself’ (Morgan, 2020: 199; original emphasis). This might be termed an attempt to reason outwards from the case, rather than inwards – and Morgan compares anthropology to psychoanalysis in terms of the awareness of the narrator’s being implicated in the events that are narrated inside a case. (We remember here Bar-Haim’s analysis of Balint and the apostolic function.) Morgan then runs through runs of cases in mathematics and medicine, showing how different iterations of case-thinking might apply in these domains. Through deliberating over analogies, runs of cases, exemplary cases, and counterfactuals (the latter of which Morgan suggests breach the limit of ‘thinking in cases’), we arrive at the realization that ‘case-based thinking or reasoning is not just a technique or tool’ but a way of ‘approaching certain kinds of materials with associated methods of reasoning found in particular sites of science’ (ibid.: 211). Specificity and context remain important to understanding what cases do and how different the various forms of ‘thinking in cases’ can be, even as they provide some of the building blocks for scientific knowledge. Morgan’s meticulous working-through of how adjudications of inside and outside are made about both case and case-maker casts further light on how other contributions to the special issue have addressed these questions. Morgan, by arguing that Forrester himself did not articulate the characteristics of thinking in cases as a ‘generic mode of scientific reasoning’ in the way that Ian Hacking, say, did for statistical thinking, celebrates Forrester’s thinking in a similar way to Bar-Haim – by ‘fill[ing] in’ that which Forrester did not himself complete or undertake.

A number of things stand out across the special issue. There is a commitment to specificity and precision, to working out exactly what it means to reason in cases in a particular temporal, spatial, or genre-focused context. (We have been intrigued to note in this regard how – without being encouraged by us as editors – contributors have drawn on the full scope of essays in Forrester’s collection.) Sometimes that has involved inserting figures (e.g. Azam, Balint, Peirce, Piaget) into lineages of case-reasoning, which helps us rethink some of the well-worn histories that are told about ‘exemplary’ case thinkers. There is also a focus on tensions between kinds of case-reasoning (within, with, from, etc.), as well as tensions within case reasoning (e.g. between the general and the specific, or the vertical and the horizontal). There is a related emphasis on the unfinished, and unfinishable, character of some case-reading and autobiographical accounts – a foregrounding of indeterminacy and ambiguity. Finally, there is a significant appreciation that certain kinds of reasoning attempted with cases often fail, and that this failure can be (historically) as instructive as success – whether with colonial administration, the diagnosis of AIDS, or trying to reason from questionnaires. Many of these contributions – and here they certainly celebrate one of Forrester’s foundational contributions to the history and philosophy of science – make both disciplines and figures somewhat strange to themselves.

To read the special issue as a whole is to enter a spiral of exchanges in which authors, cases, readers, and, indeed, Forrester himself are on the move. As we move from node to node, as sequences and runs are reworked, we are encouraged to ponder: Who has influenced whom, and how might one know? When and for what reasons do we come to remember the names of ‘subjects/objects’ of a case rather than those who brought their case to visibility? When and how does the analyst of the case fall into and become part of the case itself? And, not least, where does one find John Forrester? For Morgan (2020: 200), Robert Stoller and John Forrester at points bleed into one another (‘Forrester is not Stoller, but his writing is so closely engaged with the latter’s psychiatric mission that I am treating him as a “stand-in”’). For Bar-Haim, Forrester appears as a signature in an archive in Geneva that was at some point holding Balint’s papers – or, at least, Bar-Haim thinks he does through his spectral memory of the visitor’s book. Each of the contributors traces out a different way of relating to, thinking with (and against), and remembering Forrester. Each, in turn, sets off reverberations of his work on case-based thinking in new places.

We thank the authors for their time, patience, and exceptional scholarship. It has been a pleasure to edit and to collaborate with such a committed and thoughtful group, and a wonderful testament to the continuing vitality of John Forrester’s thought across a whole range of fields. Forrester opened ‘If p, Then What?’ by noting that his project of thinking in cases ‘started, like most large branching structures that threaten to get out of their author’s control, from small seedlings’. He argued that ‘the network has become ever more complex and difficult to map’ and asked for the reader’s ‘help in the task of managing, perhaps even pruning, the proliferation of the topics raised’ (Forrester, 1996: 1). A quarter of a century later, the vigorous growth continues, the map even more complex, the labour of watering and pruning undertaken by many hands.