Mechanism: A Visual, Lexical, and Conceptual History

By Domenico Bertoloni Meli

The mechanical philosophy first emerged as a leading player on the intellectual scene in the early modern period—seeking to explain all natural phenomena through the physics of matter and motion—and the term mechanism was coined. Over time, natural phenomena came to be understood through machine analogies and explanations and the very word mechanism, a suggestive and ambiguous expression, took on a host of different meanings. Emphasizing the important role of key ancient and early modern protagonists, from Galen to Robert Boyle, this book offers a historical investigation of the term mechanism from the late Renaissance to the end of the seventeenth century, at a time when it was used rather frequently in complex debates about the nature of the notion of the soul. In this rich and detailed study, Domenico Bertoloni Melifocuses on strategies for discussing the notion of mechanism in historically sensitive ways; the relation between mechanism, visual representation, and anatomy; the usage and meaning of the term in early modern times; and Marcello Malpighi and the problems of fecundation and generation, among the most challenging topics to investigate from a mechanistic standpoint.

• Language: English
• Publisher: University of Pittsburgh Press
• Release date: Apr 18, 2019
• ISBN: 9780822986522

Book preview

Mechanism

A Visual, Lexical, and Conceptual History

Domenico Bertoloni Meli

University of Pittsburgh Press

Published by the University of Pittsburgh Press, Pittsburgh, Pa., 15260

Copyright © 2019, University of Pittsburgh Press

All rights reserved

Manufactured in the United States of America

Printed on acid-free paper

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Cataloging-in-Publication data is available from the Library of Congress

ISBN 13: 978-0-8229-4547-5

ISBN 10: 0-8229-4547-9

Cover art: Valves in the veins. Harvey, Exercitatio anatomica de motu cordis (1628). Courtesy of the Lilly Library.

Cover design: Melissa Dias-Mandoly

ISBN-13: 978-0-8229-8652-2 (electronic)

Contents

Acknowledgments

Introduction

Chapter 1: Framing Mechanisms

Chapter 2: Mechanism and Visualization

Chapter 3: "The Very Word Mechanism"

Chapter 4: Mechanisms as Investigative Projects

Concluding Reflections

Notes

Bibliography

Index

Acknowledgments

Material leading to the first three chapters of this book stems from the A. W. Mellon Distinguished Lectures in the History of Science I had the honor of delivering in March 2016 at the University of Pittsburgh. An earlier version of chapter four was presented in May 2015 at a workshop at the École Normale Supérieure in Paris. I wish to thank Sophie Roux and the department of history and philosophy of science at Pittsburgh, especially Jim Lennox, as well as Abby Collier and all those who offered comments at my oral presentations. I also thank for useful discussions and comments Colin Allen, Tawrin Baker, Alison Calhoun, Tobias Cheung, Antonio Clericuzio, Daniel Garber, Ashley Inglehart, Roberto Lo Presti, Peter Machamer, Bill Newman, Evan Ragland, Bret Rothstein, Massimo Scalabrini, and Mark Wilson. I am grateful to the anonymous referees, who saved me from many inaccuracies and encouraged me to rethink structure and organization of my work. I am also very grateful to Bill Newman and Sophie Roux, who offered comments and criticisms to an earlier version of my manuscript. I claim sole responsibility for all remaining errors and inaccuracies.

Introduction

Over the last few decades there has been a considerable growth—perhaps an explosion—of interest in the notion of mechanism in contemporary science and the philosophy of science, notably in the life sciences and neuroscience. The number of recent philosophical studies may even justify talking of an industry, examining the definition of the term and different levels of mechanisms, from molecular to macroscopic, in a growing range of specific examples from the science literature. In their seminal paper Thinking about Mechanisms, Peter Machamer, Lindley Darden, and Carl Craver have also argued: Thinking about mechanisms offers an interesting and good way to look at the history of science. They claim that historians of science have already been writing, albeit unwittingly, as a history of the discoveries and applications of mechanisms, but they also advocate writing such a history in a more self-conscious way.¹ However, their paper has been far more influential among philosophers than among historians of science.

Mechanism is an attempt to take their claim as a starting point for a historical investigation based on the early modern period. Overall, the key focus of our term involved relying on instruments and machines to explain phenomena, excluding immaterial entities such as the soul and its faculties that had been prominent in previous accounts. The focus of my study is the time when the term mechanism started being commonly used and the mechanical philosophy emerged as a major intellectual player. This suggestive and ambiguous expression involved such different meanings that Helen Hattab has recently proposed to talk of the mechanical philosophies.²

In a letter of 1637 to the Louvain theologian Libertus Fromondus (1587–1653), Descartes referred somewhat ironically to his own Philosophie as being grossiere & Mechanique, implying a philosophy explaining phenomena by relying on shapes, sizes, and motions: this is the first known occurrence of the expression. The letter was published in 1659,³ in the same year as The Immortality of the Soul, in whose preface the Cambridge Platonist and divine Henry More referred to a Mechanick or Mechanical Philosophy; unlike Descartes, More emphasized that natural phenomena cannot be explained by excluding immaterial principles.⁴ Finally, two years later, in Certain Physiological Essays (1661), and then in several influential works, Robert Boyle adopted and popularized the expression, which became a hallmark of the new philosophy later in the century.⁵

Although there is a vast intersection between the notion of mechanism and the mechanical philosophy, emphasis on the former is often centered on single problems. In particular, whereas in general the expression mechanical philosophy involves a worldview, the term mechanism in several instances shifts the focus to the explanation of individual phenomena; the latter was often local, whereas the former tended to be global, so much so that few natural philosophers accepted it in toto.⁶ In my perspective focus on the notion of mechanism should be seen as complementary rather than alternative to the study of the mechanical philosophy, providing a more detailed analysis: some who opposed the mechanical philosophy as a global intellectual program could and did account locally for specific processes in terms of mechanisms and, conversely, some who accepted large portions of the mechanical philosophy often found individual phenomena hard to reconcile with their overall views. Joining mechanism and the mechanical philosophy enables the historian to provide a fine-grain view, enriching and problematizing our understanding of early modern concerns and debates.

While addressing the problem historically can be rewarding, it also presents specific problems that have to be carefully addressed. Reaching a satisfactory understanding of the notion of mechanism for the period I am studying and later ones is a challenging historical and philosophical task and is the goal rather than the presupposition of my work; our notion, together with those of living body and machine, took different connotations over time.

Chapter one provides an introductory theoretical framework for reflecting on mechanisms in the early modern period. It emphasizes the need to examine the notion of mechanism in conjunction with a cluster of other problematic notions and terms employed alongside it at the time. Then, in order to provide a concrete historical example, it moves back in time to Galen, a central figure whose extensive output and its philosophical implications were thoroughly studied in the early modern period. Galen’s writings and approach highlight a number of issues relevant to later debates, such as the problematic nature of the notion of the soul and its faculties, whether it is material or not, and whether it is mortal or immortal, and the need to recognize that key ancient and early modern protagonists, from Galen to Robert Boyle, applied suspension of judgment when they lacked sufficient evidence to adjudicate the matter. Thus, in many cases mechanisms and mechanistic approaches were neither dogmas nor anathemas but working hypotheses and projects worth pursuing without necessarily a predetermined answer.

Chapter two investigates the intersection between the notion of mechanism and the problem of visual representation. The verb to visualize is often used in the sense of making something, often of an abstract nature, visible to the mind or the imagination. However, it can also be used in the sense of making visible to the eye through several means, including conceptual analysis and technical devices, such as a microscope, for example. Here I use the verb in the latter sense, emphasizing the active intervention required to identify mechanisms and represent them visually. In the early modern period mechanisms were closely tied to mechanical devices and to the spatial arrangements of their parts: therefore, the issue of visual representation is closely intertwined with, though clearly not identical with, the very notion of mechanism. After briefly reviewing recent claims about the role of images in early modern Europe and the debate between David Edgerton and Michael Mahoney on the role of perspective, I focus on a crucial area, anatomy, in the long century between Andreas Vesalius and Robert Hooke. In terms of quality, size, and numbers of illustrations, Vesalius opened a new chapter in the history of anatomical representation; at the other endpoint of my narrative, Hooke investigated and represented microscopic mechanisms, and also used the very term mechanism to describe them. His usage of our term leads us to the following chapter.

The third chapter shifts the focus to a lexical study of the emergence and usage of the term mechanism in seventeenth-century Britain, where its appearance occurred especially early in specific studies as well as in broader philosophical and theological debates. While of course the concept is not coextensive with the word, there is much to be learned from this investigation, besides the actual meaning of the term, including the contexts in which it was used, the identity and professional affiliations of those who used it, and its contrast class, or the evolving sets of notions which were seen in opposition to that of mechanism. In this chapter the chronological span shifts forward, focusing mainly on the period from circa 1660 to the 1680s and on figures such as Henry More, Robert Boyle, Henry Stubbe, and Edward Tyson. The term mechanism was employed by divines and natural philosophers in the context of detailed studies but also philosophical and theological discussions about the types of explanations offered. Later sections discuss usage and meaning of our term at the turn of the century in connection with the notion of organism, documenting their shifting meanings and a growing discomfort in using the term mechanism for the living body, and very briefly in mid-eighteenth-century France in the context of Denis Diderot and Jean le Rond d’Alembert’s Encyclopédie.

Chapter four discusses a specific problem instantiating many of the previous reflections; namely, the issue of fecundation and the early stages of generation in works by Marcello Malpighi and his contemporaries. Malpighi’s writings involve visual, lexical, and conceptual issues echoing those discussed in the previous chapters. His prominent position on the anatomical stage in the second half of the century, the exceedingly problematic issue of generation, and his outline of the emergence of a self-making machine make this study highly relevant to the previous discussion. I am especially interested in the bold attempts to provide mechanistic accounts of the processes involved, despite their being at the limit of what the microscope could reveal, and often beyond it, well in the realm of speculations. Such speculations, however, can be especially helpful in revealing contemporary perspectives and assumptions. In line with my previous reflections, I seek to offer an intellectual contextualization including contemporary scholars such as William Harvey, Giovanni Alfonso Borelli, Hooke, Boyle, and Malpighi’s Bologna rivals.

A final section provides a synthetic analysis putting previous reflections under a sharper lens.

Chapter 1

Framing Mechanisms

I wish to set out my investigation with some preliminary reflections on the meaning and usage of the notion of mechanism in the early modern period. Philosophical concerns related to the notion of mechanism present many conceptual problems in their own right, though addressing the topic historically adds several specific issues to do with the changing meaning and context of usage of the term and its place in the constellation of related notions and concepts current at a time. My concern in this chapter is with how we are to talk about mechanisms, machines, and the mechanical philosophy more broadly in a historically meaningful way, one that is sensitive to these changing horizons. Of course, in no way do my reflections cover the wealth of themes and debates emerging from the historical sources. However, I hope that they could be applied to larger domains and that others may find them helpful in their own investigations.

I start from what I call the problem of labeling; namely, the study of how the term mechanism and its cognates can be used in historical narratives. I consider three strategies involving increasing nuance and sophistication: the first seeks to define the term accurately once and for all, providing normative conceptual clarity. This may be helpful in some respects; since meanings and contexts were in a state of flux, however, it may be helpful to adopt a more historically sensitive approach, involving not only the notion of mechanism in isolation, but also what we could call its contrast class, which shifted over time. A mechanism versus nonmechanism approach, too, however, while helpful in some regards, may work as a straitjacket, because over time our subjects held a range of views that is not best captured by simple dichotomies. Hence it may be appropriate to move away from a dichotomous approach and to consider both a broader spectrum of philosophical positions and a broader set of terms or notions, such as organism, for example.

In order to provide a more concrete and especially rich historical example, I review the positions Galen of Pergamon held at different times in his life on a number of issues to do with the soul and its faculties, as well as the fundamental differences between art and nature, technē and physis. At first the move to Galen in an essay focusing on the early modern period may seem surprising. However, Galen was a prolific and profound investigator both in anatomy and philosophy and is a valuable source for our reflections; moreover, his works circulated widely and were the focus of extensive debates throughout our period.

The last section identifies a number of tensions in the mechanistic program, notably between definitions and statements in principle versus practice and concrete accomplishments; between different levels of mechanistic explanations, whether limited to macroscopic dimensions or aiming at microscopic ones; in relation to shifting understanding of the term; and between imperfect human machines versus infinitely more complex and perfect divine ones. These tensions reinforce the move away from a simple dichotomous approach and point to the need for taking into account a wider spectrum of theoretical perspectives, paying attention to actors’ categories and practices.

The Problem of Labeling

Several philosophers of science have sought to provide a conceptually adequate definition of the term mechanism, one addressing systematic concerns and capturing at the same time scientific practice. In their classic paper, Machamer, Darden, and Craver have argued: What counts as a mechanism in science has developed over time and presumably will continue to do so. Their starting point is Galileo’s reliance on the Archimedean tradition and simple machines, leading to the mechanical philosophy. In later centuries chemical and electrical phenomena were added to the mix: What counts as acceptable types of entities, activities, and mechanisms change with time, and the trend continues even today.¹

The problem with some philosophers seeking to project a timeless definition onto the past is that not only the sciences and available machines but also meanings and practices shift in subtle ways in relation to broader changes in philosophical perspectives and worldviews. Over time, all such transformations can result in dramatic differences: today explanations relying on mechanism, especially those found in the life sciences, are often contrasted with lawlike explanations, which are more commonly analyzed in the philosophy of physics. In the early modern period, however, this was not the case. While most scientists today would take it for granted that physiological processes would be of a chemical and physical nature, in the seventeenth century this was the key issue at stake and several physicians and natural philosophers would have been reluctant to accept, or would have flatly denied, that complex processes like generation would occur without some immaterial guiding principle or agent—whether located in the body or more broadly in nature.

In one among his numerous publications on mechanism, Discovering Cell Mechanisms, philosopher William Bechtel provides a general definition of our term: A mechanism is a structure performing a function in virtue of its components parts, component operations, and their organization. The orchestrated functioning of the mechanism is responsible for one or more phenomena.² Here the musical metaphor emphasizes the coordinated spatial and temporal organization of the components, though in most cases this orchestra would be playing without a conductor beating the time and ensuring the timely entry of its members. Earlier in the same work Bechtel states: The key to the mechanistic approach was not the analogy of physiological systems to human made machines but the quest to explain the functioning of whole systems in terms of the operations performed by their component parts.³ Bechtel has put forward a perfectly legitimate normative claim here. My concern is whether his contention is a useful starting point for a historical analysis. A few pages later Bechtel moves to some historical examples and provides the specific example of the heartbeat to exemplify his point. Bechtel seems to suggest that Harvey’s understanding of the heartbeat was mechanistic, because it relied on the heart’s component parts, such as ventricles and valves: William Harvey had already offered his own mechanical pump model for the circulation of the blood. . . . Once Harvey established that the blood circulated, the need for a pump to move blood was recognized and the functioning heart was identified as the mechanism responsible for this phenomenon.⁴ It is not clear from these passages whether Bechtel would attribute the notion that the heart as a whole is a mechanism to Harvey (1578–1657), or only that some aspects of its action can be seen as such. As is well known, Harvey believed in a pulsative faculty of the soul responsible for its contractions, which by his own standards was nonmechanical and immaterial.⁵

In a different passage Bechtel suggested a dichotomy: "Aristotelian philosophy in particular advanced an anti-mechanistic conception of nature. It emphasized telos, the end state to be achieved by entities of nature, and the form, which resided in bodies, and determined their nature and what they did."⁶ Here mechanism is contrasted with teleology, though this dichotomy was typical of different times, such as the nineteenth century more than the early modern period, when—with the notable exception of Descartes and some of his associates—most mechanistic anatomists and natural philosophers, from Nicolaus Steno to Robert Hooke and Robert Boyle, accepted a teleological notion of mechanism seeing the body as a God-created machine. For Descartes laws of nature are due to God; the rest—including the elaborate organization of animals and the human body—follows from them.⁷

In a later passage Bechtel presents seemingly tortuous claims about the French anatomist Xavier Bichat (1771–1802):

The significance of organization for biological systems was brought home in the nineteenth century by challenges from biologists who denied that mechanisms could account for the phenomena of life. These biologists, known as vitalists, highlighted ways in which biological systems function differently than non-biological systems. Xavier Bichat (1805) is an important example. In many respects, Bichat was pursuing a program of mechanistic explanation. He attempted to explicate the behavior of different organs of the body in terms of the tissues out of which they were constructed. He decomposed these organs into different types of tissues that varied in their operations and appealed to the operations of different tissue types to explain what different organs did. But when Bichat reached the level of tissues, he abandoned the mechanistic program.⁸

In fact, Bichat was opposed to what were generally seen as mechanistic explanations and distinguished among tissues based on their vital properties; physical properties are proper to matter, while vital properties disappear with death. At the time the doctrine of vital principles or forces, also called vitalism, and mechanism were routinely contrasted, so the claim that Bichat was pursuing a program of mechanistic explanation seems curiously anachronistic. Bichat thought that the activity of organs could not be understood simply by relying on the physical properties of their component parts without attending to the vital properties of those parts. He actively opposed the mechanistic program because he deemed it erroneous.⁹ By the same token, if the defining feature of a mechanism is that it operates in virtue of its components parts, Bechtel should argue that Aristotle and Galen too, despite their teleology, in crucial respects were pursuing a program of mechanistic explanation because they attempted to explicate the behavior