Summary. From 1850 to the present, the vitalistic aspect of the circulation remains present in latent form; this is evident in the occurrence of opposing and peripheral positions as well as in elements of the dominant thought style, which have their origin in the vitalistic tradition. In conclusion, this reciprocal relation between opposing points of view is considered in connection with the ambivalence of their object, especially the complex position of the heart in the organism: the historical sequence of changing perspectives also has its foundation in the actuality itself, which ever and again transcends a one-dimensional view and demands a different explanatory model.

The history of the interpretations of the heart and circulation after Harvey and Descartes as we have seen them in outline is itself clearly characterized by an “interplay” between the vital and the mechanical aspect, or between vital and mechanistic interpretations, which have not only replaced one another periodically, but have also reciprocally influenced and enriched one another, indeed were often characteristically fused with one another. Thus although the paradigm established about the middle of the nineteenth century still dominates physiology today in a modified form, elements of both traditions are nevertheless contained in the present view of the function of the heart and circulation.

An influence on the mechanistic tradition was already contained in Harvey's discovery itself, which, as we have seen, took place in an Aristotelian-vitalistic framework and nevertheless—extracted from its framework—served as the basis for the machine model of the body. But the conception of a sensibility and excitability of the muscular tissues and hence of an autonomy of the heart, which can be influ enced by the central nervous system only in terms of modulation, also gained admittance to physiology under vitalistic premises with Harvey, Glisson, Haller, and the Romantic physiologists—and it still plays an essential role in the present conception. Finally, the attempt by Bichat and others to dethrone the “mechanical” center of the circulation directed attention once more to the vital processes and regulatory achievements of the periphery; and not least in importance, the rediscovery of the epigenetic approach and of comparative morphology in the latter part of the eighteenth century led to a better understanding of the developed heart and circulation.

But on the other side, the vitalistic tradition, too, is not without influence from its opponent.