The Origin of the Pump Analogy
The human heart is commonly viewed as a powerful pump, which typically pumps 6000 – 7500 liters of blood per day. It is admired as a supremely efficient pump, which functions to perpetuate life. What is less known is that the pump analogy, which was first employed by William Harvey, the discoverer of blood circulation and founder of modern physiology, is “in no way an integral component of his theory.”[1] Howard B. Burchell states, “Harvey’s references to mechanical analogues are cursory and never developed into a detailed comparison. His aim in such passages appears to have been illustrative – to bring a simple analogy based on a shared experience to the attention of his listeners or readers. Harvey’s vitalistic philosophy[2], including his intellectual acceptance of a supernatural generation of the heart beat, might block any thoughts that would equate the heart directly with a mechanical pump.”[3]
Within the context of Harvey’s writings and his Aristotelian beliefs, it is evident that he, who famously and for the first time compared the heart with a mechanical pump, did not reduce the heart to just that. In fact, as Thomas Edward Wright states, “Harvey was at pains to distinguish his views from those of Descartes. The Frenchman had, he declared, not only misinterpreted the movement of the heart … but also the cause of its motion. [For Harvey] the organ was an ‘autonomous living thing’ rather than a clock or a mechanical pump.”[4]
Descartes, unlike Harvey, was neither trained in anatomy nor medicine. According to Marjorie Grene, “His overall aim, however, contrary to Harvey’s, was ‘to lead the mind away from the senses,’ to separate anything ensouled or soul-like neatly from the physical, or physiological, and to establish a mathematical physics that would explain in terms of clear and distinct ideas all the operations of the world of bodies spread out in space.”[5] Descartes and Harvey operated on two distinct views, mechanical and vitalistic, respectively. Fuchs writes, “not only Harvey’s fundamental perspective, but also his interpretation of the process of circulation itself is of a thoroughly vitalistic nature, and thus deviates in essential features from today’s conception.”[6] However, “Harvey’s discovery, as well as Harvey himself, was and is seen chiefly from a perspective that was determined to a great extent not by him, but by Descartes.”[7]
From a Kuhnian perspective[8], Harvey and Descartes viewed the world from two different paradigms, and the discovery of blood circulation and the role of the heart would fit differently in each paradigm. Same observations, two different interpretations. Nonetheless, as the history of medicine advanced, “the machine paradigm developed by Descartes was indeed superimposed on Harvey’s vitalistic conception of living things so thoroughly as to make it unrecognizable.”[9]
Our conventional view of medicine and more specifically of the heart is shaped by Descartes’s mechanistic view. “Descartes acknowledges the concrete phenomena only in so far as they can be deduced from his abstract, physicalistic concept of matter. Instead of inherent principles, what governs the living as well as the dead are absolute laws of nature, which constitute a world of purely mechanical action and reaction.”[10] It is within this mechanical world, that “the single remaining function of the heart becomes an unlimited, absolute one: as a mechanical pump.”[11]
Fuchs, concisely, highlights the influence of Cartesian mechanistic thought on the physiology of the heart: “In scarcely any other sphere do we find so evident the fundamental upheaval of physiology through a physicalistic approach and the removal of the soul from the body, as Descartes had effected it, certainly not alone, but still in a paradigmatic fashion.”[12]
REFERENCES:
[1] Thomas Fuchs, The Mechanization of the Heart: Harvey and Descartes, Trans. Marjorie Grene (Rochester, NY: The University of Rochester Press, 2001), 99.
[2] The topic of Vitalism, and its distinction from Mechanism, will be discussed in future posts.
[3] Howard B. Burchell, "Mechanical and Hydraulic Analogies in Harvey's Discovery of the Circulation." Journal of the History of Medicine and Allied Sciences 36, no. 3 (1981): 260-77.
[4] Thomas E. Wright, William Harvey: A Life in Circulation. (Oxford University Press, 2013), 211.
[5] Thomas Fuchs, The Mechanization of the Heart: Harvey and Descartes, Trans. Marjorie Grene (Rochester, NY: The University of Rochester Press, 2001), xii.
[6] Ibid. P. 2
[7] Ibid.
[8] The topic of Kuhnian paradigms will be discussed in future posts.
[9] Thomas Fuchs, The Mechanization of the Heart: Harvey and Descartes, Trans. Marjorie Grene (Rochester, NY: The University of Rochester Press, 2001), 7.
[10] Ibid., P. 12
[11] Ibid., P. 199
[12] Ibid., P. 198