Francesco Gagliardi

In this article, the authors try to answer the following questions: How can an object/instance seen for the first time extend a category or update a concept? How is it possible to determine the reference of a concept that represents a behaviour? In the first case, the authors discuss the learning of inferential linguistic competence used to update a concept through an approach based on prototype theory. In the second case, the authors discuss the learning of referential linguistic competence used to determine the reference of a concept (i.e., determination of an actual behaviour) through an approach based on embodied cognition. The authors show how combining prototype-based and embodied categorization in Wittgenstein’s rule-following praxis (the individual and community dimension), linguistic learning of a concept (inferential competence), and determination of its reference (referential competence) can be traced back to the same model. Keywords Action, Categorization, Embodied Cognition, Embodiment, Linguistic Inferential Competence, Linguistic Referential Competence, Perception, Prototype Theory, Reference, Sign.

The nosological diagnosis is a particular type of nontheoretical diagnosis consisting of identifying the disease that afflicts the patient without explaining the underlying etiopathological mechanisms. Its origins are within the essentialist point of view on the nature of diseases, which dates back at least to 18th-century taxonomy studies. In this article, we propose a model of nosological diagnosis as a two-phase process composed of the categorization of inductive inferences and argumentations by analogy. In the inductive phase, disease entities are identified by means of typicality-based categorization processes, and meaningful clinical samples are learned ; in the subsequent phase, those samples are used as the bases of argumentations by analogy to obtain a diagnosis for a given patient. This model extends the prototype resemblance theory of disease including also the exemplar theory proposed in cognitive science and, moreover, it frames the clinical activity of nosological diagnosis and how it can be explained within the theory of argumentation. According to it, diagnosis based on the recognition of a typical syndrome is explained in terms of the prototype theory of categorization and the antisymmetrical argumentation by analogy, while diagnosis based on a comparison with a previous clinical case is explained by the exemplar theory of categorization and by the symmetrical argumentation by analogy.

Riassunto: Lo scopo di questo lavoro è fornire una spiegazione filosofico-cognitiva della diagnosi nosologica legando i classici temi filosofici delle forme del ragionamento scientifico con gli aspetti cognitivi del ragionamento di senso comune. In filosofia della medicina sono state proposte varie teorie della diagnosi per analizzare e spiegare il ragionamento diagnostico; una di queste è la diagnosi nosologica: un particolare tipo di diagnosi a-teorica e basata sulla similarità. In questo lavoro mostriamo come la diagnosi nosologica si possa considerare come un procedimento scientifico composto sia da processi induttivi di categorizzazione e concettualizzazione che di argomentazioni per analogia; i processi di categorizzazione coinvolti sono spiegabili usando due delle teorie dei concetti proposte nella scienza cognitiva: la teoria dei prototipi e la teoria degli esemplari; mentre le argomentazioni usate sono analogie sia simmetriche che anti-simmetriche. Infine, presentiamo un modello della diagnosi nosologica che lega in un quadro coerente queste precedenti analisi; in questo modello la diagnosi nosologica basata sul riconoscimento del quadro morboso tipico, la sindrome, è spiegata in termini di teoria dei prototipi e di argomentazioni analogiche anti-simmetriche; mentre la diagnosi nosologica basata su di un precedente caso clinico è spiegata con la teoria degli esemplari e con le usuali argomentazioni analogiche simmetriche. Parole chiave: Diagnosi; Categorizzazione; Analogia; Induzione; Nosologia Analogical Arguments and Categorization Processes in Nosological Diagnosis -: The purpose of this work is to provide a philosophical-cognitive explanation of nosological diagnosis by linking the classical philosophical themes of scientific reasoning to cognitive aspects of common sense reasoning. In philosophy of medicine, various theories of diagnosis have been proposed to analyze and explain diagnostic reasoning; one of these is nosological diagnosis: a particular type of atheoretical diagnosis based on similarity. In this paper, we show how nosological diagnosis can be considered as a scientific process composed of both inductive processes of categorization and argumentation by analogy; the categorization processes involved can be explained using two of the theories of concepts proposed in cognitive science: the theory of prototypes and the theory of exemplars; while argumentation uses both symmetrical and anti-symmetrical analogies. Finally, we present a model of nosological diagnosis that binds these previous analyses into a coherent framework; in this model, nosological diagnosis based on the recognition of a typical syndrome is explained in terms of prototype theory and anti-symmetrical analogical argumentation; while nosological diagnosis based on previous clinical case studies is explained by the theory of exemplars and the usual symmetrical analogical argumentation. Keywords: Diagnosis; Categorization; Analogy; Induction; Nosology