Long Covid/Post-Acute-Covid Syndrome as a ‘hybrid condition’ - A common framework for patients’ experience and pathophysiology

While hundreds of thousands of patients suffer from Long Covid/Post-Acute Covid-Syndrome, the condition still remains a medical conundrum. Patients’ experiences and symptoms cannot always be linked to a pathophysiological mechanism. We present a hypothesis that depicts Long Covid as a hybrid condition, which means that pathophysiology and patients’ experience are partly due to different causal pathways. On the background of neuroscience and philosophy of science research, we propose to consider the infection per se as an ‘indifferent kind’ and patients’ experiences as an ‘interactive kind’. Interactive kinds represent the interactions between the human brain, psychological experiences and sociocultural factors. This approach allows the integration of the subjective experience of Long Covid patients and the pathophysiology into a common framework. Practically, this framework may help to prevent sufferers from experiencing a devaluation of their perspective. Long Covid/Post-Acute Covid Syndrome is a real medical condition and affected patients are truly sick.

What’s my age again? Age categories as interactive kinds

This paper addresses a philosophical problem concerning the ontological status of age classification. For various purposes, people are commonly classified into categories such as “young adulthood”, “middle adulthood”, and “older adulthood”, which are defined chronologically. These age categories prima facie seem to qualify as natural kinds under a homeostatic property cluster account of natural kindhood, insofar as they capture certain biological, psychological, and social properties of people that tend to cluster together due to causal processes. However, this is challenged by the observation that age categories are historically unstable. The properties that age categories are supposed to capture are affected by healthcare and cultural developments, such that people are staying biologically, psychologically, and socially young for longer. Furthermore, the act of classifying people into age categories can bring about changes in their behaviors, which in turn alter the biological, psychological, and social properties that the categories are supposed to capture. Accordingly, I propose that age categories are best understood as interactive kinds that are influenced in dynamic ways by looping effects. I consider some implications of these looping effects for our classificatory practices concerning age, including how different disciplines may need to review the ways they define and use age categories in their inductive inferences.

Identifying the Explanatory Domain of the Looping Effect: Congruent and Incongruent Feedback Mechanisms of Interactive Kinds

Ian Hacking uses the looping effect to describe how classificatory practices in the human sciences interact with the classified people. While arguably this interaction renders the affected human kinds unstable and hence different from natural kinds, realists argue that also some prototypical natural kinds are interactive and human kinds in general are stable enough to support explanations and predictions. I defend a more fine-grained realist interpretation of interactive human kinds by arguing for an explanatory domain account of the looping effect. First, I argue that knowledge of the feedback mechanisms that mediate the looping effect can supplement, and help to identify, the applicability domain over which a kind and its property variations are stably explainable. Second, by applying this account to cross-cultural case studies of psychiatric disorders, I distinguish between congruent feedback mechanisms that explain matches between classifications and kinds, and incongruent feedback mechanisms that explain mismatches. For example, congruent mechanisms maintain Western auditory experiences in schizophrenia, whereas exporting diagnostic labels inflicts incongruence by influencing local experiences. Knowledge of the mechanisms can strengthen explanatory domains, and thereby facilitate classificatory adjustments and possible interventions on psychiatric disorders.

The Ontology of Interactive Kinds

This paper defends the notions of an interactive kind and a looping effect as features of social and human scientific classifications and aims to give a realist interpretation of them. I argue that interactive kinds can best be modeled as a special case of changing causal property cluster kinds. In order to do so, I develop a typology of looping effects according to the sort of entities that are affected, the main types of which are individual-looping, category-looping, and kind-looping. Based on this distinction, I identify interactive kinds as those causal property cluster kinds that are subjected to kind-looping.