From substitute to supplement: towards a normative reading of Merleau-Ponty’s Schneider case

How do philosophers and psychologists receive paradigmatic cases from pathology? More specifically, how are some essential features of ‘normal’ cognitive, affective or perceptual functions derived from these pathological cases? In this paper, I argue that Maurice Merleau-Ponty offers a fecund answer to this question by putting forth a logic of supplementation in pathology that distinguishes the coping behavior of the organic world in contrast to an inorganic one. Supplementation, instead of substitution, marks the world of the living, particularly in its higher forms, as it denotes a persistence through impairment governed by an organic norm. A prominent example of this appears in his reading of the patient Schneider case, a classic example from Goldstein and Gelb’s Gestalt psychology. While earlier commentators were interested in underlying whether or not Merleau-Ponty used this example to denote the persistence of a key function or the disruption of another, what has been missed, on my view, is a far more consequential point about pathologies and how they structure our relation to our world.