Thinking by cases, or: how to put social sciences back the right way up.

Thinking by case is an important book that strives to give an original solution to the central problem of the humanities: how does one generalize when starting from the description of singular configurations? Inspired by Carlo Ginzburg’s intuitions about the “indiciary paradigm”, as well as Anglo-Saxon authors (Stephen Toulmin and Albert Jonsen, Charles Ragin and Howard Becker), this collective work brings together contributions from specialists of different disciplines in an effort to endow the “cases” of human sciences with a renewed dignity, in a continuation of the weberian epistemological tradition. Drawing on a prolific casuistic tradition (moral, juridical, religious) as well as specific clinical disciplines (art history, psychoanalysis), the authors outline a “third way” between necessary deduction and arbitrary description, between objective experimentation and subjective observation. In so doing, they outline a new form of rationality, intermediary but perfectly adapted to human knowledge. Intimidated by the prestige of exact sciences, seeking a rationality they cannot be granted, the humanities have been walking upside down for some time. Dismissing the ghost of their improbable “laws”, case thinking simply offers to put these human sciences back the right way up.

It must be said that thinking by case is not the same as thinking about cases, and that thinking with singularities is not equivalent to thinking about them. This doesn’t mean that case thinking aims at something different than the particular or the singular, but rather that the book is not so much about goals, well known and perfectly identified, as about methods. The paradoxical originality of case thinking lies in its claim to knowledge of particularities obtained not through well-normed generalities, but through other singularities (considered from a certain point of view). How relevant can such a gesture of knowledge be? What is the “scientific” value of its result? Rather than a critical review, the following presentation is intended more as an invitation to the discovery of a major work.

“Thinking by case, or reasoning from the singular”,

from Jean-Claude Passeron, Jacques Revel.

In this article, Passeron and Revel try to synthesize the most general characteristics of case thinking. According to them, its logic modalities are those of a continuous argument that proceeds “through the exploration and the deepening of a singularity accessible to observation” (: 9) ^[3], in order to found a description, an explanation, an interpretation or an evaluation. The idea is not to limit the analysis, nor to think a unique case, but to “extract out of it an argumentation of a more general scope, and whose conclusions can be used again” (ibid.).

If case thinking has long been underestimated, it is because it would not comply to the major requirements of unification, homogenization and formalization of argumentation, seemingly the criteria of true scientificity. It is therefore no coincidence that its methodological rehabilitation is only recent, and contemporary to the questioning of naturalist and logicist paradigms in the humanities. In fact, there are two traditions of case thinking, that of casuistry (moral, juridical, religious), developed from ancient philosophy and rhetoric through to contemporary ethical debates, and that of clinical science (medical tradition), which was both opposed to and mingled with experimental methods in the 19^th century; and it is through the second tradition that case thinking met social sciences, at a time when these last were shaking off universal ambitions and nomological methods, and rediscovering the importance of narrative restitution in every case explanation.

How general is the case?

Passeron and Revel’s method takes on the virtuous circularity of some sort of fact-based proof. Starting with the postulate that case thinking governs the human sciences, they try to show just how relevant it is. They choose to maintain a relative amount of semantic ambiguity rather than establish an impossible initial definition, in order to focus on the operations performed when thinking by case, and on their most specific characteristics. This leads them to highlight three aspects: the case sets a problem, it requires in-depth description, and its argumentative treatment is uneasy.

To begin with, in order to form a case, a fact should not only be astonishing or disturbing: it should also, because of its occurrence, lead one to address problems. For a case calls for the institution of a new frame of reasoning, and redefines the relationship between norms and exceptions. In this way, each of Freud’s cases questions the practice of psychologists; so does the “Fustel de Coulanges” case question the historian’s writing methods (Hartog, 1988); and so does the “Pierre Rivière” case question penal psychiatry (Foucault, 1973). Secondly, the case requires an in-depth description, though this description can never claim to have treated the case’s singularity exhaustively. For the case resists all efforts to dissolve it in one of the anonymous, already normed or formalized types of general or universal thinking. In fact, whatever the generic aspects enumerated, it is always the role of a deictic (a demonstrative pronoun) to point at the peculiarity of this case, thus preventing it from being only the specification of a norm, the mere instance of a law, or a simple exemplification of a generality. Lastly, the case seems to call for specific argumentative treatment. Case descriptions have an ambiguous epistemological status since the case, indefinitely describable, does not allow necessary inferences. The problem of its argumentative status has thus divided thinkers since Aristotle (Jonsen and Toulmin, 1988). Nowadays, it is addressed in methodological and epistemological terms, dividing empirical sciences on the choice of protocol for an inventory of observable facts: biological sciences using both experimental and historical methods (physiological, neurological, physico-chemical, ethological, ecological) and human sciences which, being both statistical and historical, mix quantitative and clinical methods, formalisms and casuistries. In fact, case thinking seems to allow for “context-sensitive” semi-formalization, but not for an experimental regime of proof, based on reiteration of observations, and even less for ineffable intuition. Passeron and Revel consider its rebirth to be the effect of an “underground epistemological revolution” that has detached human sciences from positivist realism, thus paving the way for more flexible relations between world and language.

“Case making”: singularity and occurrence.

The first definition of a case, subjective and negative, stems from an effect of surprise. In fact, the case interrupts the habitual development of perceptive experience, or the planned path of a descriptive, argumentative or prescriptive discourse. This is why to identify a case as such implies an “experience of mental disadaptation”. The nature of the discrepancy is multiform and can consist in the unlikely juxtaposition of facts, or in a logical dead-end that questions a whole system of rules through the discovery of a hapax. In fact, “the force of a case is never due to a unique source” (: 16): the case is often created by a conflict between rules and their supposed applications, and by the undecidable situation thus resulting.

The singularity that makes the “case” causes perplexity by breaking the chain of generalization; it attracts attention by forcing one to withhold the available or prepared development of reasoning, and imposing a change of method. In so doing, it also stirs reflection. Now, reflecting on a case means inventing for it a path of a generalization of its own. This is the reason why the diversity of casuistry is to be explained, at least partly, by different uses of logical means: moral casuistry deals with religious sins, weberian casuistry with ideal-types, and the case studies in the American sociology of the Chicago School are something else again. Still, however different these types of casuistry may be, they share two aspects in common: singularity and the use of narrative to describe this singularity and specify the context of its occurrence. The link between these two features constitutes the logical and methodological knot in the operation of judgment that makes an occurrence a “case”.

Case as obstacle: singularity.

A case is not an example, the mere illustration of a more general theory, the singular application of a norm, the particular instance of a law. In fact, in all such configurations, the example is not given any positivity as singular, but on the contrary owes its value to its ordinaryness. From this point of view, any example can fit, since the point is to give a concrete illustration to general features, and all the attention is drawn to the general, disregarding the particular as being only a consequence or a mere application of this last ^[4]

Giving the case some positive consideration requires proceeding in exactly the opposite way, and focusing on the irreplaceable value of its singularity. The reason why a case is not a simple example is that it is itself the norm of its truth and meaning. The case is not any singularity, but a unique one. Now, obviously, every singularity is unique, strictly speaking; but the case is uniquely unique, so to speak. That is: it is its own criteria of unicity. In this respect, the case is not a particularity that could be bypassed, gently ordered, neglected or dissolved, but an ongoing enigma whose very meaning is never fully given, but requires to be constantly thought over again. One can detect a case by its resistance: “a case is an obstacle” (: 18). This is why a case calls for an interpretation, as can obviously be seen when comparing Freud’s hermeneutical approach to Charcot’s typological method.

But the case is not only what requires an interpretation: it is also at the same time the moment of a theoretical construct, as casuistry shows, the obstacles of which are also enigmas, though always in relation with a set of acquired rules: paradigmatic cases are perfectly covered by a rule, but other cases can be only partially covered by a norm, or covered by more than one at the same. This tension between ordinary and extra-ordinary cases, between rule and exception has been essential to casuistry all along its historical developments. To solve such cases of conscience, the constitutive circumstances of its singularity must be taken into account. Such a reflection does not belong to nomological deduction, but to a practical and revisable argumentation.

Accounting for a case: the narrative constraint.

To explain a case is necessarily to take into account a situation, a context. The particular framing of the plot where circumstances are inserted is what makes the case singular. The clinical method has always been keen on cases, thus confirming the importance of the narrative. Thus, in the hippocratic tradition, the history of a disease reveals the reality of the symptoms; only later does the comparison of clinical diagrams allow the constitution of types, or explanatory regularities. This singularizing procedure is also at the heart of casuistry (juridical, moral, religious), where the narrative helps to present the situation and give an understanding of how a problematic point was reached. Such procedures can be traced as far as art history (see Vasari).

The narrative dimension constitutes the case in three ways: as a privileged (though not exclusive) expression of the human experience of time, as underlined by Ricoeur ^[5]; as production, and not simply restitution of a story, since the explicit goal of grasping reality sometimes takes a fictional path; as a characteristic dimension of human sciences procedures ^[6], since the narrative reveals the proximity of clinical and historical methods, that both reconfigure collections of cases horizontally instead of vertically subsuming a case under a rule ^[7].

Case and proof.

This specific clinical dimension of case thinking is of major importance, as much for the limitations implied as for the resources involved. Its deeper meaning is that case thinking evolves in a non-popperian domain. An essential epistemological difference separates the revisable reconfiguration of historical generalities and the yellow brick road of formal generalizations (: 27). However, this logical difference has long been overlooked, mainly for two reasons. First, because the rise of experimental method together with the mathematization of natural phenomena caused the scientifically proven way to be the exclusive model of all possible demonstration. Next, because, having arrived rather late in the day, the timid human sciences tried to imitate this received model, by striving, through dangerous contortions, to translate their more original interpretations into this canonical form of rigor ^[8].

From the 17^th century on, the two different procedures of deepening a singularity and of generalizing through formalization ignored each other, and the discrepancy between the two grew stronger. On the contrary, casuistry was not submitted to the same methodological attraction as psychological and social sciences. As for history, the recent rediscovery of its narrative dimension has contributed to extend the relevance of case thinking to the other social sciences.

Finally, as far as psychoanalysis is concerned, the epistemological unease is notorious. In Freud’s works, it took the form of a hesitation between the hermeneutical narrative practice of his case studies (case thinking being the key to problems such as the therapeutic practice of clinical reflection on the etiology of neurosis), and the scientist ideology that caused him to look for a general nosography and etiology of neurosis (by measuring the frequency of typical cases and recurrent symptoms, that the experimental reasoning considers to be its basis for inferring from the particular to the general) ^[9]. Only gradually could psychoanalysis get rid of this ambiguous epistemological situation and consider its genuine logical specificity (Wildlöcher, 1990). In fact, after many hesitations ^[10], the analytical reflection is now currently heading towards unique case theories. If one treats the singular individual or the unique case as a field for cross-observation and measurement, results can truly accumulate, even if not in a strict experimental way; and this criteria of accumulation bestows psychoanalysis, but also history, sociology or anthropology, with the dignity of a scientific work, hence of knowledge.

Formal sciences and non-monotonous logics.

Nowadays, the very opposition between formal universality and singularity-based comprehension has loosened. Historical sciences, having realized they were thinking by case and that language was the milieu of their reasoning ^[11], occasionally use formalizations, for instance by inserting them as a statistical “moment” of their inquiry. One should therefore draw distinctions, not between disciplines, but between ways of reasoning and arguing. If context sciences are not liable to formal deduction or induction, it is fundamentally because they operate on cases inserted in different contexts, hence impossible to decompose into pure variables, and whose variety cannot be neutralized by a ceteris paribus clause: for them, by definition, all things cannot be equal. For this reason, they cannot claim to be experimental either (the term of “quasi-experimentation” being nothing but a placebo).

The argumentative rationality of social sciences is specific, and one can attempt to anlyse it using non-monotonous logics. Based on less demanding logical principles than those governing “strict implications”, these logics enable formalization while taking into account the relative strength of proof and the distance between contexts (inference can thus be normal, possible, probable, exceptional, impossible, etc.). In this respect, formalization of complex reasoning can be achieved to a certain extent, without disregarding nonetheless degree, order, scope and local necessity. This semi-formalization does not represent the whole of reflection, but rather constitutes a moment in a practical argumentation (see Livet)

The role of case thinking in mathematics is more paradoxical. True enough, it is different from the focus given to cases in clinical science. However, a case can appear when a fact resists all attempts to integrate it into a confined system of rules and definitions. The case’s singularity is abolished in a formal system, but the process of dismissing this singularity still reveals something of the argumentative moves of case thinking, underlining the particular deductive path which the exception forces the argument to take, and forcing it to reformulate its premises (see Karine Chemla).

Universal paradigms and local intellegibilities.

Case thinking sketches an alternative rationality by inventing an original generalization procedure, irreducible to both induction and necessary deduction.

The ambition of 20^th century sciences was to unify knowledge in vast paradigms with homogeneous language, normed proofs and demonstrations, beyond the growing fragmentation of corpuses, methods, and theories, correlative to an increasing specialization of disciplines. But this ambitious project of building a general register of experience met the obstacle of the singularity of objects.

The humanities followed this twofold movement of hope and disillusion, but the status of proof has always been very much disputed there, because of their being heirs to both the naturalism of exact sciences and the hermeneutics of philosophy (and humanities). However, the conceptual paradigms of these antagonist traditions have worn thin, as the appearance of such unconvincing epistemological tendencies as constructivism or ethno-methodology can testify. The book interprets the multiple aspects of this double decadence as the signs of a deep crisis, whose only virtue is to stress the renewed importance of case thinking.

Case and theory.

Epistemological illusions are long-lasting, and the renunciation of this unifying dream cannot prevent the existence of a persistent and diffused nostalgia for a general theory explaining every case. Because the misleading equivalence between scientific knowledge and knowledge through universal concepts is difficult to undo, the humanities continue to mimic the quest for universality, disregarding the contributions of casuistry, accused of conceptual laziness and fragmentary thinking (: 42).

In fact, in every science, concepts can play a role in scientific discovery only if they compose together a system of observation which is efficiently applicable to the world, and at the same time if the language of this description can be given a logical analysis. A fortiori in observation sciences where semantics is weaker, case thinking does not strictly separate the theoretical conceptualization from its empirical test: on the contrary, it unites both reflection and inquiry in a perpetual to-ing and fro-ing.

“The extreme and the ordinary. Remarks on the medieval case of the vanished community”,

from Yann Thomas.

Regarding the invention of the concept of “moral personality” by 12^th and 13^th century medieval jurists, Yann Thomas is less interested in the very historical beginnings of the personality fiction than in the history of cases that made its appearance possible. The case of the monastery without monks raised the issue of what might happen to a community’s rights in the case of an empty community that could however be reestablished in the future. To avoid their being taken over by the landlord of the Treasury, the monastery goods were said to belong either to the very location of the building, or to the monastery’s person, by analogy with the unclaimed succession system of Roman law. Those successions were personified to ensure the representation of a subject who no longer existed (the deceased) or did not yet exist (the undeclared heir): he who had no existence was represented by a personified heritage. Jurisprudence’s practice of “allegation” does not abide by the rule of force of precedent, according to which a rule applies to cases identical to the one it was once formulated for, following the normativist model that vertically covers all cases with norms. In fact, it proceeds by interpretative circles, association and concatenation of ideas, within the limits of the corpus of mobilisable texts. Thus appear heterogeneous configurations of objects that share having brought about not an identical norm, but a similar exemplary narrative, as if it were some kind of plot matrix.

The author’s main concern is to demonstrate that the history of the fictitious or moral personality is never fully separable from the case of the vanished community. The technical history of legal procedures and operations is less concerned with solutions than with the “movement” that secures an extraordinary case in time and makes it commonplace, because it reveals, behind the duality of legal solutions, the identity of one and the same case gesture. The “very moment when law forces its way through a dead-end by fiction” (: 46) reveals a decisive epistemological aspect of legal thought. Yann Thomas shows that the process of generalization does not correspond to the simplistic idea that one can have of it, according to which a solution once formulated for an extreme case is afterwards extended to more ordinary circumstances, and is gradually generalized into a permanent institution. In fact, the medieval cases show that the treatment of the ordinary and of the extraordinary are never separated, but on the contrary always related: what is declared in an extreme circumstance gains immediate relevance for banal circumstances, without needing any generalization. Abstractions are thus made in extreme cases that do not proceed from any generalization: if the social body of a religious or political community can be represented when it has died out, it can a fortiori be so when it survives through normal renewal. This “stabilization of the exceptional” (: 46) is not a generalization, for casuists decide immediately on a line containing the field of all possible cases beyond itself: that which is most abstract paradoxically stands on the narrow line of the most concrete.

This conjunction of the extraordinary and of the ordinary, this inclusion of the general in the singular paves the way for a new conception of the relationship between fact and law: linking rather than separating them. Not only are the occasions of law-making factual, but also the meaning of these decisions, whose form is less that of an abstract rule than that of “an exception made constant” (: 72).

“The paradigm and the general. Reflections inspired by mathematical texts of ancient China”,

from Karine Chemla.

Mathematical works that have reached us from ancient China essentially contain problems of a concrete and specific nature, followed by their numerical answers and the procedures of calculation that resolve them. Karine Chemla shows that readers saw paradigms in these text units: they saw in them general statements whose extension was determined on the basis of procedure. The increase of generalization proceeds by successive particular problems, by the time the algorithm used to solve the first is transformed to adapt to the next problem’s data. The first case serves as “paradigm”, starting from which one can identify a category of problems, solved in a general way by the algorithm’s operations. The case is then used in its twofold function: as a description, thick but limited to the data that makes each case a particular problem, but also as an index of all the series of those that are related to it through the construction of an algorithm. More broadly, the paper suggests that generalization constituted a major theoretical value for mathematicians of ancient China.

“The abuse of casuistry. A history of moral reasoning”,

from Albert R. Jonsen and Stephen Toulmin.

A few excerpts (“prologue” and first chapter) of this by now classic work are reprinted here. The book was born out of a particular experience: while taking part, at the end of the 70’s, in a national American commission working on biomedical matters and the protection of health and personal rights, Albert R. Jonsen and Stephen Toulmin noticed that the members were led to adopt a case-by-case method, quite apart from any “tyranny of principles”, whose absolute value is applicable to any case. The casuistic method allowed the commission’s members to give common advice although they came from very different horizons. Hence a true rational paradox: practical conclusions can converge whereas principles are radically incompatible. The commission’s particular judgments cannot therefore be considered to be founded on universal principles. In that case, the agreement does not derive from principles, but rather stems from a shared conception of what matters in a given situation. The paradox is due to the fact that an agreement can be reached about the decision itself, but never about the reasons of the agreement.

The authors try to solve this rational paradox, not by resorting to irrationality, but rather by sketching another rationality: the intermediary, attenuate one of practical reason. From the effective casuistic exercise of the American commission, they draw the conclusion that the practical domain requires another type of argumentation than that of deduction. In fact, while theoretical reasoning is formal, non-temporal and necessary, practical reasoning is concrete (it has an intuitive content), temporal (dependent on its context of use), presumptive (never certain). Faced with the need to invent a solution, these practical reasonings constitute case resolution methods, and they consequently require a complete and exhaustive description of the case. The validity of the argument does not rely on its belonging to a deductive chain, but on how close the likeliness of the two compared cases is. Practical reason cannot offer the rigor of theoretical reason: its properties are different, though rational. This general consideration on practical reason taken as a whole can be applied to the particular case of morality: case reasoning proves a contrario that there is no such thing as “moral geometry” in a spinozist sense, but rather only practical wisdom – aristotelian “phronèsis”.

Casuistry is based on the conviction that types of cases constitute ultimate references, and that those paradigms create basic presumptions for the resolution of similar cases to come. In so doing, it inevitably relies on a clinical art of diagnosis, common to both morals and medicine. In fact, to reduce particular medical decisions to the necessary implications of theoretical biology, or to some singular doctor’s personal wims, is to miss their specific rationality. In the same way one misses the relevance of a “practical vision of ethics” (: 124) if one only considers it equivalent to a strict moral geometry or to simple personal preferences. In reality, the argument consists in using a taxonomy and proceeding analogically, from paradigms or typical cases, to lesser known or more confused cases. It is also the clinical inference that makes moral and medical judgments presumptive and revisable in the light of a deepened experience. Finally, this presumptive dimension implies the existence of reasonable divergences in both domains: if scrupulous doctors can treat ambiguous cases in a different way, without being criticized, it is also reasonable to give space, in moral thinking, to divergences of opinion, without giving in to relativism or the arbitrariness of personal preferences.

“Collection, comparison, collective deliberation. Case treatment, from modern casuistry to consensus conferences”,

from Serge Boarini.

The paradox of casuistry lies in its having always had the ambition to think by case, without having ever tried to define “case”, nor the resolution procedures of explicated cases. The merit of Boarini’s paper is to retrace the three steps of the development of casuistry through history. He shows how both descriptive and normative properties of case “statement” evolved, from the 18^th century Cases of Consciousness Dictionaries to contemporary consensus conferences, through successive efforts towards relation, coherence and agreement.

In the case collection of dictionaries and collections of moral problems, cases, set in relation with other different singularities, are considered an exception to a preexisting norm, acknowledged and professed by the Christian tradition. But if casuistry hadn’t looked any further than the singularity of such cases, their list would have grown unmanageably. In order to restore the generality inherent to each case, casuistry therefore strove to go beyond their singularity, and to extend the resolution from each single case to others appearing in similar circumstances. Through the comparison of similar cases, casuistry could constitute typical, paradigmatic, exemplary cases, and imagine extending their solution to other cases of consciousness. This second form of casuistry satisfied the need for coherence, even if casuists did not try to make their methodology explicit. The third form of casuistry consists in treating the case as an occurrence, as something which befalls men and that they have to treat collectively, in order to elaborate a solution about which an agreement can be found. This is the contemporary form of casuistry, that favours concertation: committees of experts, juries, citizens’ conferences…

As Boarini puts it, there was a shift from a form of casuistry where the existence, before deliberation, of a set of established norms (Decalogue, Patristics…) confined reflection to a monologue, to a form of casuistry promoting a system of norms whose only foundation is the agreement reached by members in a culturally defined situation. There was therefore a transition from a monological and specialized form of casuistry to a dialogical and democratized one, in which competence is distributive. In sum, although citizens can use a casuistic method to treat morally difficult situations, there no longer exists a casuistic doctrine definitively setting the rules, not even under the contemporary figure of “expertise”.

“Casuistry in American bioethics”,

from Francis Zimmermann.

The application of ethics to biological research and medicine made its appearance in the United States in a particular religious and philosophical context, and in the wake of a pragmatic and utilitarian tradition. The method consisting in drawing arguments from the examination of difficult cases therefore diverged from that of the French National Consultative Committee, whose “advice” contributes to the elaboration of jurisprudence. Bioethicists were importing casuistry into the clinical field while at the same time conversely, its applications in medicine were revitalizing the case of conscience tradition. Zimmermann traces the developments of biomedical casuistry from Joseph Fletcher’s seminal book, Morals and Medicine that pleaded in 1954 for an ethics of situation.

Jonsen and Toulmin stressed the close resemblance between casuistic argumentation and legal plea, since both proceed by way of accumulation of good reasons in favor of a given judgment. However, they forgot to mention the constitutive role of the narrative in exposing a case. Using concepts of analysis taken from pragmatics of discourse, Zimmermann examines the combination of indirect discourse and narration used in exposing a paradigmatic case. The narrative has an argumentative function, but indirect discourse permeates the narrative with subjectivity. The two elements combine in such a way that the receiver of the presentation can identify himself with the protagonists of the case in question. Indeed, case story and expert commentaries are complementary: narrating the circumstances and discussing the principles are something like the two sides of a single coin of experience (the case). The case’s protagonists reach us through their speech and the experts’ discourse crystallizes this experience into a case. Zimmermann concludes that thinking by case can only function properly if there exists a community of speech and a space of discussion between the different receivers of the narratives and commentaries that constitute bioethics.

“The Lives of Vasari, history of art and the ‘unnamed science’ of case”,

from Jean-Philippe Antoine.

Vasari’s predecessors (Dante, Boccace, Sacchetti) took into account the exemplarity of an artistic case without explicitly placing it in a series: for them, the case was an absolute singularity, unthinkable, and above all passive, noticeable from the outside in a network of spatial and temporal circumstances. Vasari, on the contrary, can be considered the first modern historian of art, since his Lives of the painters, sculptors and architects have installed an unprecedented logic of cases, based on their serialization and the comparison of their differences.

Compared to Ghiberti who, by drawing a parallel between ancient and modern art, would think of events using a binary figure of return (the old and the new), Vasari innovates by demultiplying the possibilities of diversification. In fact, the “time difference” that bestows the vasarian logic with dynamism and mobility, as shown in the lives of Cimabue and Giotto, is less the manifestation of a history, even cyclical, than the principle of a series of qualitative variations, where cases end up being singularized, as can be seen in the parallel between the contemporary excellencies of Michel-Angelo and Raphaël. Writing art history does not consist in compiling anecdotes in linear chronicles, but in weaving cases by defining and ordaining multiplicities, without pretending to extract them from the course of time.

Ever since Vasari, this case logic has continued to characterize the different avatars of reflection on art. Thus, even though Winckelmann explicitly built his art history project on a criticism of Vasari’s Lives (choosing to write only about things actually seen), he does not revert to an antiquarian logic. The roman collections he examines are not the incarnation of ideal beauty, nor a mere collection of fragmentary material traces of the past, but objects which enable to distinguish in the Greek case an exemplary culture of art, defined by the conjunction of a series of periods and a series of locations. Art history is not a compilation, but a system of styles, whose perfection depends on accidental circumstances. Giovanni Morelli, whom Carlo Ginzburg compares to Sherlock Holmes in this respect, acquired an astonishing capacity of expertise by elaborating, through minute attention to details, a real science of artistic “manners”. Wölfflin abandons the observation of individual styles and problems of attribution: he replaces a “history of names“ with a general history of “forms of vision”, constituting abstract series structured by oppositions (for instance that of the pictorial and of the linear). Here again we find the same gesture: constituting new homogeneous series by pointing out unnoticed resemblances, and distinguishing, on this new basis, new heterogeneous and singular cases which had escaped observation, and thus defining periods amongst the relative disorder of styles and schools. This gesture is also reproduced, each in his own way, by Aby Warburg, Erwin Panofsky, Émile Mâle…

This case logic, both historical and critical, uses two successive operations: constituting homogenous series from the perception of resemblances between different objects, and stressing the heterogeneity of the series’ members, thus inventing a new series, based this time on heterogeneities considered as such. Though they are part of social science in general, such forms of discourse about art concentrate on cases in a model way, by relating art to singular individuation.

“Psychological and psychoanalytical case study (19^th century – early 20^th century)”,

from Jacqueline Carroy.

Following recent works which use interactionism to investigate the history of psychology in a new way, Carroy tries to distinguish the characteristics of the psychological case. She begins by examining the way in which case studies were established at the end of the 19th and at the beginning of the 20^th century in psychology, psychiatry or psychoanalysis, concentrating specifically on the psyche of individuals, dead or alive. The case was subjected to a realistic imperative and could not be invented. Its first characteristic, therefore, lay in the existence of a relationship between observer and observed, or therapist and patient, or even a self-inquiry.

The author then sketches a history of case studies, showing how these generate collections that privilege the common or the exceptional (hospital patients, famous men), but can also be based on self-observation (dream notation, criminal or sexual pervert confessions). In opposition to this kind of observation or self-observation, that presumes that the observer does not interfere with the observed, there are certain narrative accounts of therapies that take into consideration the patient’s relationship with the therapist and assign to it a curative dimension, according to different modalities (Freud, Janet). In this respect, one of the interesting points of Carroy’s analysis is the perspective she gives Freud’s work, replacing him inside a larger set, and showing he did not invent case thinking, but rather inherited it as a fundamental tendency of his time: his (and Janet’s) originality lies elsewhere, in the shift he introduced from case to case history.

Carroy finally considers the subsequent questioning of published cases, comparing revisions of Charcot’s observations, of certain famous dream accounts and of examples taken from the history of psychoanalytical cases (Anna O., the wolf man). In her view, if the case always seems to allow for undoing and redoing, it is because it relies on an unsurpassable heuristic tension between private and public knowledge. Taking this distinction from Gérard Holton’s Scientific Imagination, Carroy suggests that if psychological or psychoanalytical case studies never establish any stabilized assumption it is because they are always “science in the making”.

“The different forms of reasoning by case”,

from Pierre Livet.

One of the interests of Pierre Livet’s work is an effort of semantic clarification. In fact, there are different forms of case reasoning, and each of them requires to be examined in its own right.

The first type concerns arguments going from the general to the particular, and conversely. The operations then consist in subsuming a singular case under a general rule or a universal concept, putting it in a class, and eventually showing the obstacles met in so doing. The argument goes through the list of all categorized cases (for instance, by showing that a geometrical property is verified for a type of entity, then for another one, then all types). To determine the case in its specificity supposes another argument, and Pierre Livet suggests to approach the singular case as much by the properties it accepts and the inferences it allows (the case being used to reinforce) as by those it refuses, and so considering the case as something which undoes normal inferences (and not as in Popper, as a rigid falsificator). One can then shift from the particular to the general by using the case to revise rules: the argument is not an induction (that requires starting from multiple cases) since it stems from a single concrete case, and the goal is not to validate a general hypothesis, but to show how a general rule must be adjusted in a singular situation, or how diverse general hypotheses modify one another in relation to the considered case.

The second type concerns arguments based on prototypes. They stem from a particular but central case, presenting certain similarities with other presented cases. By estimating the degree of similarity in each dimension of resemblance, one can define how close each item is to the prototype in certain respects, and how far from it in others: thus establishing a scale of similarity. A prototype is a concrete example about which new properties can be discovered. It is not necessarily used in all its concrete aspects, but rather relatively to “the radiant set of cases” (: 236) which it brings together through partial and non transitive similarity (the cases not being necessarily similar amongst themselves). A fact can also be stylized, but new properties cannot then be discovered about it, since stylization reduces the concrete to a few operations and parameters. Whereas the prototype is concrete and varies with the context, the stylized fact evacuates the context by reducing it to a few specifications. Whereas the prototype cannot be formalized, the stylized fact is a skeleton of a situation whose parameters are chosen in order to formalize the typical operations supposed to take place in it.

Arguments of the third type, proceeding by revision, normality and exception, tackle a problem that the two previous types of reasoning cannot solve: certain features of an example can contradict some features of the prototype, instead of being only their attenuated forms (for instance, an individual who is not a soldier may be a conscience objector). In this situation, if one starts from a general rule, one must recognize its exceptions, and know when to decide whether it is an exception and when to change the rule (if the exceptions are too numerous); if one starts from a prototype, one must define what absence of feature, and to what degree, can help decide whether or not the fact belongs to the prototype’s domain of similarity. In both cases, non-monotonous logics, with which normal inference loses its automaticity to become conditional, can be very useful because they provide procedures of revision based on ramifications and not on rigid classes (as in the case of probabilistic revision). This type of logic presupposes a notion of context, separating normal and exceptional inferences. Formalization becomes possible, and can be used as a criteria of coherence for an argument, but never as a criteria of preference between two coherent inferences. The casuists’ mistake is to have missed this limit of formalization, and to have sought after a unique system of casuistry, by building ramifications of rules into sub-rules. For moral science is not fixed, and can need to be modified, or revised through a projection out of present morals into future morals: such a problem belongs to the last type of cases.

The last type of case reasoning, proceeding by double revision, solves the particular problem of knowing in what perspective, and to what extent, one can propose a perspective that integrates certain changes of viewpoint in advance. To face this challenge, one must consider that a case’s singularity lies in two aspects: on the one hand, it induces a revision of normal anticipations and, on the other hand, through its different possible extensions, it orders them in a way that retrospectively modifies the previous orders of evaluation. This double revision theory (panoramic revision in relation to different possible worlds, and whiplash revision in relation to the present) takes into account the role of emotions and can help to solve certain rational paradoxes (Allais’ lottery paradox). Livet’s aim is principally formalization: he sees in the connector “by” of Jean-Yves Girard’s linear logic the archetypal social connector, quite representative of symbolization, and makes it the heart of revisable case thinking. The principal form of case reasoning thus consists in a back-and-forth movement between a concrete case, dispersed items covered by the case, and the reevaluation of the case’s potentialities depending on the way one takes into account its incoherencies (as normal or problematic).

“The register of knowledge. Figures of knowledge and the grasp of reality”,

from Claude Imbert.

Today’s tendency to privilege the “framework” of cases in the humanities is the sign of a silent epistemological revolution, whose ramified origins and issues the author retraces here. Cases shape a set of events by applying to it a diversity of complementary disciplines. They constitute an empirical knowledge that does not proceed by documentary saturation, and that remains more interested by the exactness of its approach than by decision. Cases certainly result from a legal modality of knowledge, but from a judgment separated from the rigid kantian ground of “experience”. Following Foucault’s intuitions, Claude Imbert shows that the break occurred on the question of anthropology, which is divided between the wish to objectivate behaviours and the wish to subjectivate what bestows them with intelligence and normativity.

Unity of the book.

At the end of this important work, many questions remain unresolved, one of them concerning the unity of the book. In fact, case thinking covers a vast domain, since it pervades not only moral, but also legal and formal sciences. This is ambiguous enough. Firstly because, although case thinking is operative in every descriptive science (including medicine), nothing is said about earth sciences, or paleontology and theories of evolution, that also combine a deictic concern with a sense of history. Secondly, because the authors insist on the humanities, while the domain of case thinking is in fact much larger: its operations regulate not only descriptive disciplines (art history, psychology, sociology, history), but also prescriptive ones (law, moral, religious commandments). Where is, therefore, the unity of case thinking’

The answer is to be looked for in the works that directly inspired this book. Carlo Ginzburg, by stressing the existence of the “indiciary paradigm”, sought to escape a devastating alternative between rationalism and irrationalism. Jonsen and Toulmin, as far as they are concerned, explicitly referred to Aristotle’s practical philosophy. Apart from formal disciplines, where case thinking is subsidiary (so the authors themselves confess), one must draw the conclusion that case thinking concerns every domain of human action and human behavior: as the object of ethical wisdom, of juridical prescription, or of objective knowledge (historical, social, psychological). Case thinking might then be another name for practical reason, a reason of the probable, the fragile, the temporary, often overshadowed by the power of formal thinking that nonetheless fails to fully absorb practical logic. A number of authors (Kant or Aristotle for instance) have underlined the difference between the two forms of rationality. Still, in its contemporary form (as in Ricoeur or Habermas for example), such a rationality of action, though distinct from the rationality of knowledge, does not fail to intersect with the latter, and one can consider that the human sciences occupy precisely this location, and that their notorious epistemologic ambiguity is due to the very mix which characterizes it (half-theoretical, half-practical). In this practical reason, how would the authors locate humanities in relationship to ethics, law, even politics, that this book explicitly acknowledges as figures of case thinking’

Finally, how can one account for the absence of reflection on linguistics in such a seminal book? In Passeron and Revel’s treatment of language there is mention of the “formal clearness” of linguistics, but also a move to refuse its “triumphant” extension to other social systems through generalized semiotics, and to distance themselves from the renewal of formal logics, accused of being responsible for “the new ambition of language and discourse sciences” (: 39). Yet, they do also remark that the arguments of human sciences are shaped in a “natural language”, and this point is notoriously central to Passeron, let alone Zimmermann’s use of discourse pragmatics. Could the primary material of case thinking itself possibly resist case thinking? On the contrary, could one not apply case thinking to words themselves, and to their very literary constructions? Does the fact that language, more than a material or a tool of case thinking, is its very element and, so to speak, its milieu, not make the absence of reflection about linguistics not all the more regrettable’