On Excentricity and ExplanationReply To Sass's and Walter's Comments
In his commentary, Louis Sass points out some aspects of excentricity that are important to keep in mind when applying the notion to schizophrenia.
First, it is true that the failure of the excentric position may not be equated with the naïve egocentricity of Piaget's young child—it is not a "regression" to an earlier developmental stage. On the contrary, paranoid delusion is only possible because the patients had already acquired the excentric position before, for this is what leads them to see themselves "in others' eyes"—namely being observed, spied at, persecuted by them. The problem is rather that their perspective-taking is unbound (sometimes also termed "overmentalizing"), forces itself on them, and may not be neutralized by referring to mere coincidence. This implies a peculiar intertwinement of perspective-taking and subjectivization, not mere egocentricity.
Second, Sass is equally right in emphasizing the dialectical character of the schizophrenic alienation. Pathologies are never mere deficiencies. The subjectivization undergone by the patients certainly establishes, on the positive side, a unique outlook on the world which they may well be aware of, indeed which they may even foster to a certain extent. This creates a kind of "excentricity" in the usual sense of the word—stepping outside of the common sense with its inherent normativity. Thus, on the one hand there is an excentricity as a structure of human beings in general—the excentric position as conceived by Plessner, which enables perspective-taking and the co-constitution of a shared reality. On the other hand, this general structure may also be regarded as a presupposition both for certain personality types with their "off center" attitudes and for the "idionomia" (Stanghellini) and the withdrawal of schizophrenia patients into an autistic world of their own. Hence, the excentricity which enables intersubjectivity and the sociality of the human being also allows for a retreat into an "ídios kósmos."
In the second commentary, Henrik Walter addresses the topic of schizophrenic delusion from a neurobiological point of view and takes issue with what he calls a merely descriptive approach—which, as he somewhat condescendingly adds, contains no more than the usual knowledge acquired by a psychiatric intern in his first year, apart from some "fancy terminology" of enactivism.
Now, it is fairly easy to give a simplified account of a complex analysis to the point where it seems to present nothing new. However, the lynchpin of my article is the assumption that understanding delusions requires first an in-depth analysis of the reality constitution achieved by normal perception, [End Page 89] which in turn is best explained by an enactive (i.e., interactive and intersubjective) account. Such an investigation claims to achieve much more than a mere description sensu Jaspers—namely, to point out the conditions of possibility for the subjectivization of schizophrenic perception and its loss of the intersubjective co-constitution of reality. These conditions are founded precisely in the structure of normal perception. This is of course not a neurobiological explanation—it was neither the aim of the article to provide such a neurobiological account nor to exclude it—but it is an explanation of the genesis and altered structure of delusion, not a mere description.
Granted, this explanation is not complete—it could indeed be supplemented by neurobiological components (which, for their part, cannot claim completeness either without taking the patients' subjectivity and intersubjectivity into account). The important misconception here is to embrace the highly problematic Jaspersian opposition of (phenomenological) "mere description" and (neuroscientific) "actual explanation". Phenomenological accounts, in particular if enriched by enactive and genetic concepts, may well explicate the implicit structure of pathological phenomena and thus contribute to bridging the explanatory gap between symptoms and correlated neural processes (on this kind of explanation, see Parnas & Sass , Fuchs ). This is not to say that "neurocognitive explanations of delusions necessarily must fail", as Walter wrongly interprets my view. However, the enactive approach would require such explanations to go beyond mere disturbed information processing within the brain and conceive of delusion as the result of a disturbed interaction of brain, body, and environment—or in short, of disturbed sense-making. Neurocognitive explanations fail only if they claim to provide the whole story.
Although citing only his own articles when addressing the "4E cognition" approach, it remains to be noted that Walter has not been particularly conspicuous as a proponent of this approach so far. Maybe some further reading might be necessary, which would keep him from misusing this label to denote his clearly internalist account of the "predictive coding" concept. While an enactive reading of predictive coding may well be possible (see Bruineberg, Kiverstein, & Rietveld, 2016; Gal lagher & Bower, 2017), the way in which Walter uses this theory is certainly not enactive. That is because he still adheres to a general representationalist notion of perception as information processing done by the brain. We are told that we have "implemented internal world models" from the very start, which are adapted in the course of our interactions with the environment. Walter seems to suppose that any "top-down" neural processing is enough to make a theory "enactive," but this is a mistake. Enactive theories of perception are much more radical in that they reject the very division of labor between perception, cognition, and action as supposed by representationalist accounts of "internal world models." Only if one first accepts a gap between "mind" and "world" does this gap subsequently require bridging by representations and internal models. Walter's internalist account of predictive coding thus leaves unchallenged the theory that delusions should be regarded as maladaptive beliefs that misrepresent the world. It is precisely this misconception of delusions that I have tried to amend. Ironically then, Walter's commentary thus attests of the importance of first properly investigating our theoretical presuppositions on the nature of perception for our understanding of delusions.
Thomas Fuchs, MD, PhD, is Karl Jaspers Professor of Philosophy and Psychiatry and Head of the Section "Phenomenological Psychopathology and Psychotherapy" at the Psychiatric Department, University of Heidelberg. His major research interests include phenomenological psychopathology and psychology as well as phenomenology and cognitive neuroscience. Recent books: Ecology of the brain (forthcoming) Oxford: Oxford University Press. C. Durt, T. Fuchs, C. Tewes (Eds.) (2018) Embodiment, enaction, and culture. Investigating the constitution of the shared world. Cambridge, MA: MIT Press.