The complexity of cognitive emulation of human diagnostic reasoning is the major challenge in the implementation of computer-based programs for diagnostic advice in medicine. We here present an epistemological model of diagnosis with the ultimate goal of defining a high-level language for cognitive and computational primitives. The diagnostic task proceeds through three different phases: hypotheses generation, hypotheses testing and hypotheses closure. Hypotheses generation has the inferential form of abduction (from findings to hypotheses) constrained under the criterion (...) of plausibility. Hypotheses testing is achieved by a deductive inference (from generated hypotheses to expected findings), followed by an eliminative induction, constrained under the criterion of covering, which matches expected findings against patient''s findings to select the best explanation. Hypotheses closure is a deductive-inductive type of inference very similar to the inferences operating in hypotheses testing. In this case induction matches the consequences of the generated hypotheses against the patient''s characteristics or preferences under the criterion of utility. By using the language exploited in this epistemological model, it is possible to describe the cognitive tasks underlying the most influential knowledge-based diagnostic systems. (shrink)

In most areas of medicine, the physician's primary task is to diagnose the patient's presenting problem by correctly identifying the underlying pathology causing that problem. Diagnoses are established through a process of correlating the information obtained from an interview with the patient about his history of illness and circumstances, with additional evidence of the underlying disease derived from physical examination findings and/or the results of laboratory investigations and diagnostic imaging. In contemporary health care, various movements that call for a (...) shift in clinical care away from underlying disease pathology toward understanding people and their experience of disease are receiving growing... (shrink)

Diagnostic errors are more frequently a result of the clinician's failure to combine medical knowledge adequately than of data inaccuracy. Diagnostic reasoning studies are valuable to understand and improve diagnostic reasoning. However, most diagnostic reasoning studies are characterized by some limitations which make these studies seem more simple than diagnostic reasoning in real life situations actually is. These limitations are connected both to the failure to acknowledge components of knowledge used in (...) clinical practice as well as to acknowledge the physician-patient relationship's influence on clinical knowledge and on the reasoning process itself. In addition the modes of reasoning described in these studies frequently is oversimplified. In this paper three simplistic and competing models of diagnostic reasoning are analyzed and criticized, followed by an evaluation of two alternative models proposing a combined view. (shrink)

Background Most studies on medical reasoning focus on contemporary allopathic practitioners. Here, the significance of diagnostic sense in Nizāmī ‘Arūzī’s Four Discourses (Chahār Maqāle), an influential text that circulated widely throughout the Islamic world, is explored. Methods After a brief introduction, key passages are translated on how doctors should cultivate analytical skills. Results Nizāmī ‘Arūzī cites three sources of diagnostic authority: (1) education in the texts of medical experts, (2) formal logic and (3) belief in the power (...) of God. Conclusions ‘Arūzī’s methods, though rooted in a religious faith that may seem foreign to contemporary doctors and educators, has much to recommend regarding its clarity of approach, its high ethical standards and expectations of doctors, and its commitment to best practices for the patient. Crosscultural studies of medical education and professionalism can offer valuable insights by demonstrating how doctors across history and geography have grappled with the common concerns of diagnosis and treatment. (shrink)

An investigation is presented in which a computer simulation model (DIAGNOSER) is used to develop and test predictions for behavior of subjects in a task of medical diagnosis. The first experiment employed a process‐tracing methodology in order to compare hypothesis generation and evaluation behavior of DIAGNOSER with individuals at different levels of expertise (students, trainees, experts). A second experiment performed with only DIAGNOSER identified conditions under which errors in reasoning in the first experiment could be related to interpretation of (...) specific data items. Predictions derived from DIAGNOSER's performance were tested in a third experiment with a new sample of subjects. Data from the three experiments indicated that (1) form of diagnostic reasoning was similar for all subjects trained in medicine and for the simulation model, (2) substance of diagnostic reasoning employed by the simulation model was parable with that of the more expert subjects, and (3) errors in subjects' reasoning were attributable to deficiencies in disease knowledge and the interpretation of specific patient data cues predicted by the simulation model. (shrink)

Two facets of diagnostic reasoning related to scientific thinking are recognizing the difference between confounded and unconfounded evidence and selecting appropriate interventions that could provide learners the evidence necessary to make an appropriate causal conclusion. The present study investigates both these abilities in 3- to 6-year-old children. We found both competence and developmental progress in the capacity to recognize that evidence is confounded. Similarly, children performed above chance in some tasks testing for the selection of a controlled test (...) of a hypothesis. However, these capacities were unrelated, suggesting that preschoolers’ nascent understanding of the control-of-variables strategy may not be driven by a metacognitive understanding that confounded evidence does not support a unique causal conclusion, and requires further investigation. (shrink)

Recent work in cognitive psychology and experimental semantics indicates that people do not categorize natural kinds solely by virtue of their purported scientific essence. Two attempts have been made to explain away the data by appealing to the idea that participants in these studies are reasoning diagnostically. I will argue that an appeal to diagnostic reasoning will likely not help to explain away the data.

Many recent developments in artificial intelligence research are relevant for traditional issues in the philosophy of science. One of the developments in AI research we want to focus on in this article is diagnostic reasoning, which we consider to be of interest for the theory of explanation in general and for an understanding of explanatory arguments in economic science in particular. Usually, explanation is primarily discussed in terms of deductive inferences in classical logic. However, in recent AI research (...) it is observed that a diagnostic explanation is actually quite different from deductive reasoning. In diagnostic reasoning the emphasis is on restoring consistency rather than on deduction. Intuitively speaking, the problem diagnostic reasoning is concerned with is the following. Consider a description of a system in which the normal behavior of the system is characterized and an observation that conflicts with this normal behavior. The diagnostic problem is to determine which of the components of the system can, when assumed to be functioning abnormally, account for the conflicting observation. A diagnosis is a set of allegedly malfunctioning components that can be used to restore the consistency of the system description and the observation. In this article, this kind of reasoning is formalized and we show its importance for the theory of explanation. We will show how the diagnosis nondeductively explains the discrepancy between the observed and the correct system behavior. The article also shows the relevance of the subject for real scientific arguments by showing that examples of diagnostic reasoning can be found in Friedman's Theory of the Consumption Function. Moreover, it places the philosophical implications of diagnostic reasoning in the context of Mill's aprioristic methodology. (shrink)

Background: Causal reasoning as a way to make a diagnosis seems convincing. Modern medicine depends on the search for causes of disease and it seems fair to assert that such knowledge is employed in diagnosis. Causal reasoning as it has been presented neglects to some extent the conception of multifactorial disease causes. Goal: The purpose of this paper is to analyze aspects of causation relevant for discussing causal reasoning in a diagnostic context.

In lieu of an abstract, here is a brief excerpt of the content:Diagnostic WannabesJennifer Radden, PhD (bio)Saunders explores challenges for the clinician faced with self-styled sufferers from attention deficit hyperactivity disorder, post-traumatic stress disorder, bipolar disorder, autism spectrum disorder (ASD), and fibromyalgia. The diagnostic system was not meant to be used as “a scaffold for identity,” she points out. Yet wannabe patients now step into the clinic wielding self-proclaimed diagnoses as social identities. Saunders explains the context where such (...) phenomena arise, and offers guidelines for clinicians addressing this new reality. To do so, she enlists Rashed’s innovative normative approach to the so-called boundary problem of assigning, and providing justification for, the contested line between normal and disordered. The boundary problem itself seems to rise to prominence during our current era of increasingly dimensional thinking, it is worth noting, with psychiatric diagnoses taken to refer to points on a continuum, rather than to discrete categorical disease entities.On the likely sources of these ‘diagnostic’ social identities, as well as reasons why certain diagnoses attach to them more commonly than others, Saunders points to social trends (including what she asserts to be a “post-stigma” cultural environment), the failure of efforts to identify neurobiological markers for psychiatric disorder, the ubiquity of social media, the algorithms themselves, and the hyperconnected existence of contemporary times. Such narratives also offer the comforts of a sense of belonging and explanations for perceived inadequacies, she rightly observes.Despite today’s virtual and other inducements, the problem introduced here is not an entirely new one. The first part of the seventeenth century in Europe saw an apparent “epidemic” of what was known as “melancholy,” a condition associated with the spleen, whose symptoms loosely resembled those of today’s depression and anxiety. Much of this suffering was undeniably real, but much was a fashionable, identity-conferring pose. “Every distemper of the body now is complicated with spleen,” the poet John Donne ironically observes in a letter dated 1622, “and when we were young men we scarce ever heard of the spleen. In our declinations now, every accident is accompanied with heavy clouds of melancholy”1 (Gosse, 2019). By then, the Melancholic Man (or homo melancholicus), with his surfeit of spleen, was an unmistakable character type—or social identity, as we would now say. Recognized and saluted in centuries-long literary and illustrative traditions, the type was an anchoring element of the humoral medicine which, despite the gradual emergence of more empirical science, had endured since Galenic times.Melancholy’s closest descendants, affective depressive and anxiety disorders, are today less evident among the troubling identities Saunders discusses—somewhat preempted, she points out, by more cognitively-based diagnoses such as ASD. [End Page 279] This is itself an ironic reminder of the vagaries of cultural attitudes, cautioning us to remember the broader context where these particular social identities are selected for emulation and adoption.The lure of the melancholy man’s2 social identity is well understood: already normalized, within the humoral system in which excess black bile afflicted roughly one in four people, it had been valorized for centuries—arguably by Aristotelian writing (in the dubious ‘Problems’), during the Renaissance by Ficino, and Shakespeare—even by Freud in his 1916 ‘Mourning and Melancholia.’ Through most of Western history, the positive attributes and benefits of the dark moods of melancholy have needed no further explaining or justifying. They glow with glamorous associations.Applying Rashed’s conditions for appropriately acknowledging and recognizing the fit of a person’s chosen social identity, Saunders‘ guidance for clinicians clarifies boundary matters. And it illustrates how to understand, regulate and communicate the appropriate norms in ways that can dissuade those whose personal growth and mental health are not served by claiming such identities.With at least some of the popular social identities Saunders describes, I think we can helpfully continue the comparison with the homo melancholicus. For the ‘neurodiversity’ rhetoric of our own times contains forces promoting both the normalization and the valorization of syndromes such as ASD. Pointing to analogies with differences of gender, ethnicity and culture, neurodiversity theorizing argues for a respect for, and appreciation of, difference. Mental or cognitive variations are equally natural and valuable, it is... (shrink)

Visual aids can improve comprehension of risks associated with medical treatments, screenings, and lifestyles. Do visual aids also help decision makers accurately assess their risk comprehension? That is, do visual aids help them become well calibrated? To address these questions, we investigated the benefits of visual aids displaying numerical information and measured accuracy of self-assessment of diagnostic inferences (i.e., metacognitive judgment calibration) controlling for individual differences in numeracy. Participants included 108 patients who made diagnostic inferences about three medical (...) tests on the basis of information about the sensitivity and false-positive rate of the tests and disease prevalence. Half of the patients received the information in numbers without a visual aid, while the other half received numbers along with a grid representing the numerical information. In the numerical condition, many patients --especially those with low numeracy-- misinterpreted the predictive value of the tests and profoundly overestimated the accuracy of their inferences. Metacognitive judgment calibration mediated the relationship between numeracy and accuracy of diagnostic inferences. In contrast, in the visual aid condition, patients at all levels of numeracy showed high-levels of inferential accuracy and metacognitive judgment calibration. Results indicate that accurate metacognitive assessment may explain the beneficial effects of visual aids and numeracy --a result that accords with theory suggesting that metacognition is an essential part of risk literacy. We conclude that well-designed risk communications can inform patients about health-relevant numerical information while helping them assess the quality of their own risk comprehension. (shrink)

In an analysis of artificially intelligent systems for medical diagnostics and treatment planning we argue that patients should be able to exercise a right to withdraw from AI diagnostics and treatment planning for reasons related to (1) the physician’s role in the patients’ formation of and acting on personal preferences and values, (2) the bias and opacity problem of AI systems, and (3) rational concerns about the future societal effects of introducing AI systems in the health care sector.

We raise a problem of applicability of RCTs to validate nuclear diagnostic imaging tests. In spite of the wide application of PET and other similar techniques that use radiopharmaceuticals for diagnostic purposes, RCT-based evidence on their validity is sparse. We claim that this is due to a general conceptual problem that we call Prevalence of Treatment, which arises in connection with designing RCTs for testing any diagnostic procedure in the present context of medical research, and is particularly (...) apparent in this case. We also identify three practical reasons why RCTs do not qualify as the best option for PET validation, which have to do with specific characteristics of nuclear diagnostic imaging, and of radiopharmaceuticals. The paper is meant to contribute both to the philosophical discussion on the EBM hierarchy of evidence, and on the specific debate on radiopharmaceuticals in nuclear medicine. (shrink)

Classifying Madness (Springer, 2005) concerns philosophical problems with the Diagnostic and Statistical Manual of Mental Disorders, more commonly known as the D.S.M. The D.S.M. is published by the American Psychiatric Association and aims to list and describe all mental disorders. The first half of Classifying Madness asks whether the project of constructing a classification of mental disorders that reflects natural distinctions makes sense. Chapters examine the nature of mental illness, and also consider whether mental disorders fall into natural kinds. (...) The second half of the book addresses epistemic worries. Even supposing a natural classification system to be possible in principle, there may be reasons to be suspicious of the categories included in the D.S.M. I examine the extent to which the D.S.M. depends on psychiatric theory, and look at how it has been shaped by social and financial factors. I aim to be critical of the D.S.M. without being antagonistic towards it. Ultimately, however, I am forced to conclude that although the D.S.M. is of immense practical importance, it is unlikely to come to reflect the natural structure of mental disorders. (shrink)

A diagnostic judgment of a teacher can be seen as an inference from manifest observable evidence on a student’s behavior to his or her latent traits. This can be described by a Bayesian model of in-ference: The teacher starts from a set of assumptions on the student (hypotheses), with subjective probabilities for each hypothesis (priors). Subsequently, he or she uses observed evidence (stu-dents’ responses to tasks) and knowledge on conditional probabilities of this evidence (likelihoods) to revise these assumptions. Many (...) systematic deviations from this model (biases, e.g. base-rate neglect, inverse fallacy) are reported in literature on Bayesian reasoning. In a teacher’s situation the information (hypotheses, priors, likelihoods) is usually not explicitly represented numerically (as in most research on Bayesian reasoning), but only by qualitative esti-mations in the mind of the teacher. In our study, we ask to which extent individuals (approximately) apply a rational Bayesian strategy or resort on other biased strategies of processing information for their diagnostic judgments. We explicitly pose this question with respect to non-numerical settings. To investigate this question, we developed a scenario that visually displays all relevant information (hypotheses, priors, likelihoods) in a graphically displayed hypothesis space (called “hypothegon”) – without recurring to numerical representations or mathematical procedures. 42 pre-service teach-ers were asked to judge the plausibility of different misconceptions of six students based on their responses to decimal comparison tasks (e.g. 3.39 > 3.4). Applying a Bayesian classification proce-dure, we identified three updating strategies: A Bayesian update strategy (BUS, processing all probabilities), a combined evidence strategy (CES, ignoring the prior probabilities but including all likelihoods), and a single evidence strategy (SES, only using the likelihood of the most probable hypothesis). In study 1, an instruction on the relevance of using all probabilities (priors and likelihoods) only weakly increased the processing of more information. In study 2, we found strong evidence that a visual explication of the prior-likelihood interaction led to an increase of processing the interaction of all relevant information. These results show that the phenomena found in general research on Bayesian reasoning in numerical settings extend to diagnostic judgments in non-numerical settings. (shrink)

The paper explores the relation between reason and action as it emerges from the texts of Āyurveda. Life or Ayus (commonly understood as life-span) is primary subject matter of Ayurveda. Life is a locus of experience, action and disposition. Experiences and actions are differentially determined by dispositions that characterize the organism; otherwise all living organisms will be identical. Ayus of each living being is uniquely individual and remains constant between birth and death. In this journey, upkeep of ayus is the (...) purpose of Āyurveda or science of life. Ayurveda is a science of experienced matter as well as of experienced body. The living body is critically dependent on the influx of matter for its upkeep. Āyurveda offers a conceptual system to reason about balance and imbalances of the system and the causal role of the material flux through the system. This sensate matter is causally open and makes room for definite causal role for the individual and the effective insertion of the felt-purpose of action. Some of the strengths of Ayurveda are brought forth in the paper such as (a) reasoning out the compatibility between the bodily processes and the selection of the natural products for diet and drug, (b) role for heuristics in medical diagnosis, which takes into cognizance the particularity of each living body and the teleology evident in the very act of diagnostic reasoning. The paper shows that Āyurvedic theory is built on experiential datum whereas scientific medical theory is built on experience-independent datum. Āyurveda explores causal efficacy of ‘secondary qualities’ whereas scientific medicine explores causal efficacy of ‘primary qualities’. The actionable experiential reasoning is at the foundations of Āyurveda whereas modern medical science is ab initio saddled with difficult ‘hiatus theoreticus’ between theory and practice. For Ayurveda it is experience of qualities that discloses behavior of matter. The types of qualities that appear in experience have a special significance for theorizing about the actions of matter with the help of qualities. The paper explores the relation between experience of qualities and the method of science. It shows how efficacy of medical practice is based on the foundational stance of experiential realism in theory. To bring the point home, the paper borrows Aristotalian concepts to show how the relation between phantasm and phronesis is honored in the very theory of Āyurveda. (shrink)

A brief overview is provided of sociological and historical critiques of Western psychiatry before focusing on pre-empirical, non-empirical and empirical aspects of psychiatric diagnosis. These are then discussed using the analytical devices of the ontic fallacy, the epistemic fallacy and generative mechanisms. It is concluded that mental disorders do not really exist but particular presenting problems of unintelligibility, interpersonal dysfunction and common human misery, in particular social contexts, recur in modern life and thus constitute real problems for those intimately implicated (...) and for social order. These require new ways of understanding, beyond the option of deconstruction, which could displace categorical reasoning and be sensitive to causes, meanings and their situated social contexts. The paper concludes with an outline of an alternative future for research into mental health problems, which could be informed by critical realism. (shrink)

Partiendo de las deficiencias detectadas en la realización de la discusión diagnóstica por los estudiantes de Medicina, determinadas en un estudio previo realizado en la Facultad de Ciencias Médicas de Camagüey, se diseñó una metodología para perfeccionar la realización de la discusión diagnóstica en la carrera de Medicina, en la cual se incluyeron un sistema de tareas y las acciones que permiten alcanzar el desarrollo de las habilidades relacionadas con la misma. También se reflejaron las formas organizativas de enseñanza y (...) las actividades de educación en el trabajo en las que se deben abordar los elementos de la metodología, así como la propuesta de criterios evaluativos para estas habilidades, y otros aspectos como la ejecución y evaluación de la metodología. Se consideró que esta propuesta metodológica puede constituir una herramienta útil para los profesores en la conducción del proceso de adquisición de las habilidades de razonamiento clínico en los estudiantes. On the basis of the deficiencies identified in the realization of the diagnostic discussion by medical students, which were determined in a previous study carried out in the Faculty of medical sciences of Camagüey, a methodology was designed to improve the realization of the diagnostic discussion in Medicine degree, which included a set of tasks and actions that allow the development of skills related to it. Also, the teaching organization forms and education activities at work that must deal with methodology elements were stated, as well as the proposal of assessment criteria for these skills and other aspects like assessment and implementation of methodology. It was considered that this methodology can be used as a useful tool for teachers as guides in the process of students´ acquirement of clinical reasoning skills. (shrink)

With regard to current debates on the ethical implementation of AI, especially two demands are linked: the call for explainability and for ultimate human responsibility. In the medical field, both are condensed into the role of one person: It is the physician to whom AI output should be explainable and who should thus bear ultimate responsibility for diagnostic or treatment decisions that are based on such AI output. In this article, we argue that a black box AI indeed creates (...) a rationally irresolvable epistemic situation for the physician involved. Specifically, strange errors that are occasionally made by AI sometimes detach its output from human reasoning. Within this article it is further argued that such an epistemic situation is problematic in the context of ultimate human responsibility. Since said strange errors limit the promises of explainability and the concept of explainability frequently appears irrelevant or insignificant when applied to a diverse set of medical applications, we deem it worthwhile to reconsider the call for ultimate human responsibility. (shrink)

Over the past few decades, cognitive science has identified several forms of reasoning that make essential use of conceptual knowledge. Despite significant theoretical and empirical progress, there is still no unified framework for understanding how concepts are used in reasoning. This paper argues that the theory of conceptual spaces is capable of filling this gap. Our strategy is to demonstrate how various inference mechanisms which clearly rely on conceptual information—including similarity, typicality, and diagnosticity-based reasoning—can be modeled using (...) principles derived from conceptual spaces. Our first topic analyzes the role of expectations in inductive reasoning and their relation to the structure of our concepts. We examine the relationship between using generic expressions in natural language and common-sense reasoning as a second topic. We propose that the strength of a generic can be described by distances between properties and prototypes in conceptual spaces. Our third topic is category-based induction. We demonstrate that the theory of conceptual spaces can serve as a comprehensive model for this type of reasoning. The final topic is analogy. We review some proposals in this area, present a taxonomy of analogical relations, and show how to model them in terms of distances in conceptual spaces. We also briefly discuss the implications of the model for reasoning with concepts in artificial systems. (shrink)

We distinguish three aspects of medical diagnosis: generating new diagnostic hypotheses, selecting hypotheses for further pursuit, and evaluating their probability in light of the available evidence. Drawing on Peirce’s account of abduction, we argue that hypothesis generation is amenable to normative analysis: physicians need to make good decisions about when and how to generate new diagnostic hypothesis as well as when to stop. The intertwining relationship between the generation and selection of diagnostic hypotheses is illustrated through the (...) analysis of a detailed clinical case study. This interaction is not adequately captured by the existing probabilistic, decision-theoretic models of the threshold approach to clinical decision-making. Instead, we propose to conceptualize medical diagnosis in terms of strategic reasoning. (shrink)

I reconstruct the discovery of the Higgs boson by the ATLAS collaboration at CERN as the application of a series of inferences from effects to causes. I show to what extent such diagnostic causal inferences can be based on well established knowledge gained in previous experiments. To this extent, causal reasoning can be used to infer the existence of entities, rather than just causal relationships between them. The resulting account relies on the principle of causality, attributes only a (...) heuristic role to the theory’s predictions, and shows how, and to what extent, data selection can be used to exclude alternative causes, even “unconceived” ones. (shrink)

In medical diagnostic examination three main stages may be distinguished: (a) initial exploration, (b) hypothesis-directed investigation, and (c) final diagnosis making. The purpose of this work is to study some methodological problems concerning the second of the above stages of the diagnosis and to prepare a background for a mathematical model [30] of this process.In diagnostic problem solving, the reasoning proceeds along the main lines traced by some initial suggestions and passes through various intermediate elements which are (...) connected with one another forming ramifying chains and nets of inferences and hypotheses. Such a complex mental construction is based on laws which form medical knowledge and reflect various regularities and relations, causal, structural, functional, and others. (shrink)

The development and publication of Diagnostic and Statistical Manual of Mental Disorders, fifth edition produced a peak in mainstream media interest in psychiatry, and a large and generally critical set of scientific commentaries. The coverage has focused mainly on the expansion of some categories, and loosening of some criteria, which together may lead to more people receiving diagnoses, and accompanying accusations of the medicalisation of normal living. Instructions given to members of DSM-5 work groups appear to have encouraged this.1 (...) This has not been the only source of disquiet. The influence of the pharmaceutical industry on the members of the appointees to DSM diagnostic work groups, which constructed the new rubrics, has caused concern,2 as remuneration and insurance coverage in the USA depends partly on DSM diagnosis, and the pharmaceutical industry has been accused of encouraging the development of new diagnoses as a way to increase profitability.3 Societal impact has been an explicit part of the development of DSM-5, as outlined in the article in this issue.4 Reasons for decisions by DSM-5 workgroups have included enabling sufferers to receive treatment which would not be available without a DSM diagnosis , or …. (shrink)

Two approaches to the study of diagnostic thinking are compared, one mainly propositional, namely that of Patel and Groen (1986), the other mainly semantic, that of Lemieux and Bordage (1986). Patel and Groen analyzed the linear dimension of cardiologists' discourses while solving a case of acute bacterial endocarditis, that is, the before and after propositional rules. A secondary analysis of two of their pothophysiological protocols is done using structural semantic techniques from Lemieux and Bordage where the vertical dimension of (...) the discourses is analyzed, that is, the levels of meaning or semantic axes. Contrary to Patel and Groen's position, making an accurate diagnosis is not explained in terms of pure forward reasoning through networks of causal rules, but by means of networks of semantic qualities abstracted from the symptoms and signs. The semantic qualities operate in the clinician's mind in terms of binary oppositions (e.g., sudden-gradual, unilateral-bilateral) whereby each pair of properties constitutes a semantic axis (e.g., sudden-gradual). The successful diagnosticians are those who use the most diversified and pertinent set of semantic axes and, therefore, have a deeper representation of the problem. (shrink)

This article presents a computational model of the learning of diagnostic knowledge, based on observations of human operators engaged in real-world troubleshooting tasks. We present a model of problem solving and learning in which the reasoner introspects about its own performance on the problem-solving task, identifies what it needs to learn to improve its performance, formulates learning goals to acquire the required knowledge, and pursues its learning goals using multiple learning strategies. The model is implemented in a computer system (...) which provides a case study based on observations of troubleshooting operators and protocol analysis of the data gathered in the test area of an operational electronics manufacturing plant. The model not only addresses issues in human learning, but, in addition, is computationally justified as a uniform, extensible framework for multistrategy learning. (shrink)

The author recommends an involved study of logical fallacies in order to provide a database of testable hypotheses for error reasoning. The purpose of the study is to make the study of logical fallacies accessible to a wider audience. Following a recent study conducted by Ludwig Schlecht, the author presents a diagnostic method to illustrate how an argument can be fallacious from the breach of particular rational principles. The diagnosis method also serves as investigation into other forms of (...) argumentative fallacies and the author suggests it could later be the basis for training programs for undergraduate students in logic courses. (shrink)

This work examines the influence of reference dependence, including value selection bias and congruence effects, on diagnostic reasoning. Across two studies, we explored how dependence on the initial problem structure influences the ability to solve simplified precursors to the more traditional Bayesian reasoning problems. Analyses evaluated accuracy and types of response errors as a function of congruence between the problem presentation and question of interest, amount of information, need for computation, and individual differences in numerical abilities. Across (...) all problem variations, there was consistent and strong evidence of a value selection bias in that incorrect responses almost always conformed to values that were provided in the problem rather than other errors including those related to computation. The most consistent and unexpected error across all conditions in the first experiment was that people were often more likely to utilize the superordinate value as part of their solution rather than the anticipated reference class values. This resulted in a weakened effect of congruence, with relatively low accuracy even in congruent conditions, and a dominant response error of the superordinate value. Experiment 2 confirmed that the introduction of a new sample drew attention away from the provided reference class, increasing reliance on the overall sample size. This superordinate preference error, along with the benefit of repeating the PPV reference class within the question, demonstrated the importance of reference dependence based on the salience of information within the response prompt. Throughout, higher numerical skills were generally associated with higher accuracy, whether calculations were required or not. (shrink)

The target article focuses exclusively on System 2 and on reasoning rationality: the ability to reach valid conclusions from available information, as in the Wason task. The decision-theoretic concept of coherence rationality requires beliefs to be consistent, even when they are assessed one at a time. Judgment heuristics belong to System 1, and help explain the incoherence of intuitive beliefs.

Recent research shows that in reasoning tasks, subjects usually produce an initial intuitive answer, accompanied by a metacognitive experience, which has been called feeling of rightness. This paper is aimed at exploring the complimentary experience of feeling of error, that is, the spontaneous, subtle sensation of cognitive uneasiness arising from conflict detection during thinking. We investigate FOE in two studies with the “bat-and-ball” reasoning task, in its standard and isomorphic control versions. Study 1 is a generation study, in (...) which participants are asked to generate their own response. Study 2 is an evaluation study, in which participants are asked to choose between two conflicting answers. In each study, the FOE is measured by the FOE questionnaire. Results show that the FOE is significantly present in the standard B&B task when participants give a wrong answer, that our questionnaire can measure it, and furthermore, that it is diagnostic of genuine error. (shrink)

Until now, philosophical debate about human embryonic stem cell (hESC) research has largely been limited to its ethical dimensions and implications. Although the importance and urgency of these ethical debates should not be underestimated, the almost undivided attention that mainstream and feminist philosophers have paid to the ethical dimensions of hESC research suggests that the only philosophically interesting questions and concerns about it are by and large ethical in nature. My argument goes some distance to challenge the assumption that ethical (...) considerations alone must be foregrounded in philosophical discussions about hESC research by introducing a critical stance on the epistemological and ontological assumptions that underlie and condition it. A central aim of the paper is to show how Foucault's insights into knowledge-power, taken in combination with Hacking's claims about styles of reasoning, can make these assumptions evident, as well as cast light on their potentially deleterious implications for disabled people. Arguing in this way also enables me to draw out constitutive effects of research on stem cells, that is, to indicate how the discursive practices surrounding research on stem cells, as well as the technology itself, contribute to the constitution of impairment. (shrink)

The minimally conscious sta te (MCS) is usually ascribed when a patientwith brain damage exhibits obser vable volitional behaviors that predict recovery ofcognitive funct ions. Nevertheless, a patient with brain damage who lacks motorcapacit y might nonetheless be in MCS. For this reason, some clinicians use neuralsignals as a communicative means for MCS ascription. For instance, a vegetativestate patient is diagnosed with MCS if activity in the motor area is observed whenthe instruction to imagine wiggling toes is given. The validi (...) ty of using neuralsignals in ascribing MCS requires a special sort of inference. That is, no-reportparadigmatic assessments must have inductively strong ways of inferring a pur-ported informationa l content from the observed neural signal that grounds the factthat the patient has top-down cognitive control (or residual volition). Shannon’smathemat ical theory of communication and Bayes’ theorem reveals the formalstructure of neural communication. On the basis of relevant data from the neuro-science literature, I conclude that the formal structure combined with the data showsthat neural signals can be used as a communicative means for operational diagnosticcriteria for MCS ascription. (shrink)

In this paper we argue that dissociative identity disorder (DID) is best interpreted as a causal model of a (possible) post-traumatic psychological process, as a mechanical model of an abnormal psychological condition. From this perspective we examine and criticize the evidential status of DID, and we demonstrate that there is really no good reason to believe that anyone has ever suffered from DID so understood. This is so because the proponents of DID violate basic methodological principles of good causal modeling. (...) When every ounce of your concentration is fixed upon blasting a winged pig out of the sky, you do not question its species' ontological status. James Morrow, City of Truth (1990). (shrink)

I present two philosophical arguments that Antisocial Personality Disorder (ASPD) and Psychopathy can be expected to be culturally variable. I argue that the ways in which people with ASPD and psychopaths can be expected to act will vary with societal values and culture. In the second part of the chapter, I will briefly review some of the empirical literature on cross-cultural variation in ASPD and psychopathy and argue that it is consistent with my philosophical claims. My conclusion in this chapter (...) is that methods of diagnosis will need to be culturally specific. A diagnostic instrument (such as the PCL-R or DSM) should not be uncritically employed in cultures that are very different from those in which it was initially developed. (shrink)

Although there is consensus on the fact that ionizing radiation used in radiological examinations can affect health, the stochastic nature of risk makes it difficult to anticipate and assess specific health implications for patients. The issue of radiation protection is peculiar as any dosage received in life is cumulative, the sensitivity to radiation is highly variable from one person to another, and between 20 % and 50 % of radiological examinations appear not to be necessary. In this context, one might (...) reasonably assume that information and patient consent would play an important role in regulating radiological practice. However, there is to date no clear consensus regarding the nature and content of—or even need for—consent by patients exposed to ionizing radiation. While law and ethics support the same principles for respecting the dignity of the person, in the context of radiology practice, they do not provide a consistent message to guide clinical decision-making. This article analyzes the issue of healthcare professionals’ duty to inform and obtain patient consent for radiological examinations. Considering that both law and ethics have as one of their aims to protect vulnerable populations, it is important that they begin to give greater attention to issues raised by the use of ionizing radiation in medicine. While the situation in Canada serves as a backdrop for a reflective analysis of the problem, the conclusions are pertinent for professional practice in other jurisdictions because the principles underlying health law and jurisprudence are fairly general. (shrink)