Pump, person and Parfit: why the constitutive heart matters

The historical view of the heart as a source and repository of characteristics of individual persons remains prevalent in speech and literature. A more recent scientific view regards the heart as just a replaceable mechanical device, supporting a hydraulic system (the pump-view). To accept the pump-view is to reduce the historical view of the heart, and reference to it, to metaphor. To address whether this conclusion is justified, this paper investigates what constitutes an individual person over time and whether the heart has any role in that constitution. While some physical continuity may be necessary, most philosophers agree that our 'personal identity' is conferred through the persistence of 'psychological' characteristics predominantly through memory. Memory is constituted through the interplay of external and internal sensory experience-to which the heart is a major contributor. On scientific grounds alone this sensory role for the heart makes the pump-view incomplete. If our persistence as a person reflects the totality of experience codified through memory, and the heart is a central source of the internal component of that experience, then the pump-view is also misleading since the heart plays some constitutive role. More widely, if what fundamentally matters for our survival as persons is just psychological continuity, then the pump-view is irrelevant. While a 'supportive heart' may be necessary for continued embodiment, it is on the constitutive role of the heart, as part of a unique internal experience, that our individuation as persons depends.