The senses of common sense

Abstract

The Sixth study brings back the phenomenon of common sense, which until now I have examined in its social dimension, into the realm of corporeality. Merleau-Polity's work is essential to this point. This study aims at answering the following question: Does the experience of disconnectedness from the others that takes place in the realm of the social life of schizophrenic persons share a common root with the experience of disconnectedness from oneself taking place in the realm of self-awareness? These are the two roots of schizophrenic psychopathology: (i) disorders in pre-reflective self-consciousness, implying morbid objectification of sensations and emotions and of bodily and mental functions, and (ii) disorders in sense integration, more precisely in sensory-to-sensory and sensory-to-motor integration, implying disorders of attunement (which is based on simulation routines, i.e. the coupling between action perception, simulation of action, and understanding of intentions), and consequently autism. What is still missing in today's psychopathology is a panoramic view on these two phenomena – anomalous self-experience and autism. The Aristotelian concept of koiné aisthesis may provide the philosophical background of such a panoramic view. In Aristotle, koiné aisthesis (common sense) has two different functions: the first is to combine the different modalities (koiné dunamis) of specific senses (aisthesis idia) like hearing, touching, seeing, etc., the second is to accompany each sensation with the awareness of the sensation itself. The first function of koiné aisthesis affords the experience of a perceptual unity, and the perception of those qualities which belong to all sense modalities (‘common sensations’) and do not belong to one specific sense modality such as loudness (hearing), brightness (seeing), smoothness (touching), etc. The second function affords the experience of oneself as the subject of one's own perceptual experiences – it is the source of self-awareness. What we call self-consciousness is for Aristotle a direct perception of oneself while perceiving something, ‘the common power accompanying all the senses, by which we perceive that we are seeing and hearing’. Self-consciousness is for Aristotle sensory self-consciousness; it belongs to the animal principle of sentience. It is an embodied act, an immediate act which happens in the flesh and which Aristotle elsewhere compares with touch, and as such must be distinguished from, noetic self-consciousness, which is disembodied and intellectual. This is a crucial point both in Aristotle's philosophy of mind, and also, as we will see, in the phenomenology of schizophrenia.Aristotle's koiné aisthesis, in the light of recent developmental psychology and neurobiology, is not only the basis for the integrated perception of the physical world, but also for the meaningful perception of the others’ actions in the social world, since it is the basis for the phenomenon of emotional affective attunement which is the prerequisite for the emergence of the social self and of intersubjectivity. Here, the work of Merleau-Ponty is of crucial importance: the mutual constraints between sensory self-consciousness (especially bodily awareness) and intersubjectivity are outlined, i.e. the circular process of the emergence of a core and a social self. Abnormal attunement may de-structure self-perception (but the reverse is also true: attunement may help to re-structure one's own self-experience). It is also suggested that abnormal bodily sensations (coenesthopathies), a very common phenomenon in early phases of schizophrenia, may affect the inter-corporeal resonance on which attunement is based. Developmental psychology and psychopathological data legitimate to consider that disordered koiné aisthesis is the common ground for schizophrenic anomalous phenomena in self- and social experience. Aristotle's koiné aisthesis is not only the basis for the integrated perception of the physical world, but also for the meaningful perception of others’ behaviours in the social world. This concept is originally expressing both embodiment and attunement to the social world. The bodily and the social selves share the same experiential foundation.Connecting the abnormalities of the schizophrenic persons’ phenomenal and social self to the concept of koiné aisthesis, and bridging the latter to contemporary developmental psychology, is an invitation to linking the phenomenological account of schizophrenic disorders to the neurodevelopmental hypothesis of schizophrenia. koiné aisthesis is the ante litteram philosophical construct to express the neurobiological concept of intra- and intermodal binding, which is the basis of the hypothesis of the neurodevelopmental origin of schizophrenia. My phenomenological understanding of schizophrenia is largely compatible with the neurodevelopmental hypothesis, since intra- and intermodal binding can be seen as the root for sensory self-consciousness and for social consciousness, the latter through the phenomenon of attunement. Intermodal integration of signals is a prerequisite for the development of normal self-perception and for intersubjective abilities.