E - Vitalism and Mechanism Between 1700 and 1850

Summary

Summary. After a backward glance at the first phase of the reception of the circulation, we will follow the interaction of the vitalistic and mechanistic aspects in the period from 1700 to 1850. Within a brief time in or around 1750, after a period of increasingly disputed dominance, the mechanistic paradigm was replaced by vitalism. Above all, vitalism was shaped by the concepts of “irritability” and “sensibility,” through which—without being aware of it—Albrecht von Haller had again taken up Harvey's conception in modified form. An essential contribution to this development was the inability of the mechanistic orientation to provide a satisfactory explanation of cardiac action. Haller demonstrates conclusively its independence of the central nervous system and, like Harvey, interprets it as an autonomous stimulus-response reaction of blood and cardiac muscle. The vitalism that was attached—contrary to his intention—to Haller's results and concepts not only takes up again Harvey's explanation of cardiac action, but also his basic morphogenetic point of view. The attempt is made to deduce the functions of the organs from their development, and the movement of the heart in particular from the primary, autonomous movement of blood in the egg (C.F. Wolff). Once more, the blood is often considered the sensitive basic material of the organism, itself alive.

In a further radicalization of the vitalistic approach, the physiology of the Romantic period (from about 1800) then contrasts the heart as mechanically acting center with the periphery as the proper sphere of vital processes. In 1801, Xavier Bichat attributes the circulation itself to a “peripheral heart” to which the central heart is subordinated as a supplementary stimulus. Under the guidance of the motif of polarity, indicated by Harvey but now made explicit in the language of Naturphilosophie, German physiologists now also develop various models opposed to the previous conception of the circulation (P.F.v.Walther, L.Oken, J.H.Oesterreicher, C.H. Schultz, C.G. Carus).

About the middle of the nineteenth century, a new thought-style again comes to dominate, a thought-style that is related, despite modifications, to the Cartesian-mechanistic tradition. With his exposition of the movement of the heart and blood, F. Magendie can serve as typical representative of this conception. Nevertheless, in the sense of the interaction of different aspects, the new paradigm does not fail to be influenced by its predecessor.