What do you think?
Rate this book
Cambridge Studies in Philosophy and Biology
Discovering Cell Mechanisms: The Creation of Modern Cell Biology
Between 1940 and 1970, pioneers in the new field of cell biology discovered the operative parts of cells and their contributions to cell life. Cell biology was a revolutionary science in its own right, but in this book, it also provides fuel for yet another revolution, one that focuses on the very conception of science itself. Laws have traditionally been regarded as the primary vehicle of explanation, but in the emerging philosophy of science it is mechanisms that do the explanatory work. William Bechtel emphasizes how mechanisms were discovered by cell biologists.
- GenresBiology
334 pages, Hardcover
First published October 10, 2005
33 people want to read
Ratings & Reviews
Friends & Following
Create a free account to discover what your friends think of this book!
Community Reviews
Displaying 1 of 1 review
December 7, 2022
It may seem strange, in view of how deeply contemporary civilization bears the impress of modern empirical science, that the meaning of some of its basic conceptions should still be subject to debate and, indeed, that understanding of them among the community of philosophers of science should have witnessed major advances as recently as the past twenty years. Yet this very thing holds true, at least as regards the core concept of mechanism. The mechanical philosophy of nature first came to prominence during the pre-Newtonian era of the seventeenth century. At that time, one naïvely supposed that force could be transmitted solely by mechanical contact, in the collisions of corpuscules. By the close of the nineteenth century, however, the mechanical philosophy remained intact and indeed reigned supreme, after the erstwhile development of electrodynamics had thrust upon physicists the recognition that force could be exerted at a distance and that what really matters is that Newton’s laws permit an effective mathematical description of the interaction of corporeal bodies through their intermediary fields. In other words, what one currently means by mechanical is a degree of freedom entering into an action functional – a somewhat rarefied concept, compared to its extremely concrete starting point!
This is all well and good, if one be only a physicist. The great successes of modern physics however, not least in atomic physics after the advent of the quantum mechanics, encourage everyone to suppose that all natural phenomena ought to explicable in reductionistic terms, that is to say, mechanically. Meanwhile, after the second world war, the discipline of cell biology underwent a revolution propelled by advances in instrumentation made possible by the application of quantum physics to technology. The noted philosopher of science William Bechtel tells the story of these discoveries admirably in his Discovering Cell Mechanisms: The Creation of Modern Cell Biology (Cambridge Studies in Philosophy and Biology, originally published in 2006). The author figures as part of a small band of scholars who since the 1990’s have reconceived our vision of the nature of scientific inquiry, based on inspiration from biology as their model. Previously, received views in the philosophy of science had been dominated by physics, from the Vienna Circle to Hempel and Salmon – what scarcely seems unusual, given the tremendous growth of physics itself during the first half of the twentieth century. Thus, philosophy of science pursued in this mold tends to center on the questions of the status of determinism and reduction.
Why these are not so relevant in cell biology: as Aristotle stresses in his organon, the method it is desirable to follow in a given field ought to be appropriate to the subject matter. Nothing could be worse than to judge a claim to knowledge by an alien standard. For in fact systems characterized by the concurrence of very many relevant degrees of freedom confront us with a phenomenon sui generis, pace Dirac’s influential dicta to the effect that chemistry has henceforward been reduced to a branch of quantum physics:
The fundamental laws necessary for the mathematical treatment of a large part of physics and the whole of chemistry are thus completely known, and the difficulty lies only in the fact that application of these laws leads to equations that are too complex to be solved. [Quantum mechanics of many-electron systems, Proceedings of the Royal Society of London 73A, 714-733 (1929)]
The great systematician Ernst Mayr underscores in his Toward a New Philosophy of Biology: Observations of an Evolutionist (Harvard University Press, 1988) the marks that constitute biology as an autonomous scientific discipline: the exceptional complexity of living systems, their organization into populations, their possession of a genetic program, the precedence of a comparative method over the experimental, the relevance of high-level concepts that cannot readily be reduced to low-level terms (such a meiosis in cell reproduction), the different status of general laws and theories and lastly, the presence of adaptedness and teleology (or function, if one prefer) [pp. 8-23]. In view of these points, one could counter Dirac by saying that he might be right about chemistry, but certainly not about biology.
Typical of biology is that, in place of exact calculation and formulaic laws, it revolves largely around qualitative comprehension. Not that quantitative measurements are irrelevant; rather they play a different and more auxiliary role: to inform insight by fitting into a perceivable pattern rarely subject to precise prediction as part of a mathematical formalism. Natural laws, such as they may occur in biology, constitute generalizations often admitting of exceptions, expressed through natural language instead of through an analytical formula. Therefore, one has good antecedent grounds to expect that the contours of a philosophy of science drawing principally on biology rather than on physics ought to look very different.
The role of mechanism in particular is the crux. Why? Bechtel:
The science of cell biology is very different from the textbook image of science, including that advanced in traditional philosophy of science. That picture, grounded on some of the great successes of the scientific revolution and subsequent developments in some areas of physics, emphasizes bold unifying generalization – the laws of nature. Newton’s laws of motion promised to explain all motion, both terrestrial and celestial. The laws of thermodynamics and electromagnetism are similarly broad in their sweep. In biology, Darwin’s insight that evolution by natural selection occurs when there is heritable variation in fitness has provided a similarly powerful unifying generalization. However, most areas of biology – including cell biology – do not fit into this picture. Instead of unifying generalizations, cell biology offers detailed accounts of complex mechanisms in which different component parts perform specific operations, which are organized and orchestrated so that a given cell type can accomplish the functions essential for its life. Not elegant generalizations, but exquisitely detailed accounts of mechanisms, are the products. This difference in product has broad implications for our overall understanding of science, including the challenges of generating evidence, advancing new hypotheses and theories, and evaluating and revising them. [p. 2]
Why does cell biology count as a new discipline, beginning in the 1940’s and having attained this status by the late 1960’s?
The investigators who created cell biology were strongly committed to inquiry that related knowledge of the parts of the cell (organelles) and the chemical operations that took place in those parts. The methodologies that had been so successful in the early decades of biochemistry involved extracting the responsible enzymes and substrates from cells and studying reactions that did not depend on the specifics of cell structure. So for many biochemists, cells were unimportant. A number of cytologists, on the other hand, were eager to relate cell parts to chemical operations, but for the most part they lacked the tools to make the connections. Thus, despite the focus on cell structure and function by cytology and biochemistry...in 1940 there remained a terra incognita between these two fields. [p. 14]
Bechtel’s other major concern centers on what it took to get there:
The new research techniques pose both an engineering and an epistemic challenge. As in prototypical engineering tasks, in order to use the ultracentrifuge or the electron microscope, researchers had to figure out ways to accomplish new tasks – for example, to release the contents of cells from the cell membrane without disrupting internal structures and to stain cell components so that they would differentially diffract electrons. Engineering tasks like these give rise to the epistemic challenge of showing that the results reflect the phenomenon of interest and are not artifactual. [p. 15]
The theoretical chapter two starts out with historical conceptions of mechanism, paying special attention to Descartes, Boyle, Newton [p. 20ff]. The conception of mechanism current in the twentieth century draws on Hume and the logical empiricists. As of the time of Bechtel’s training, an influential voice on the topic of mechanism was the philosopher of science Wesley Salmon, whose conception goes beyond that of the seventeenth century. Bechtel discusses why [p. 24ff]. After this historical review, Bechtel’s carefully wrought definition of his terms reads like a series of patent claims:
A mechanism is a structure performing a function in virtue of its component parts, component operations and their organization. The orchestrated functioning of the mechanism is responsible for one or more phenomena.
Moreover:
· the component parts of the mechanism are those that figure in producing a phenomenon of interest;
· each component operation involves at least one component part. Typically there is an active part that initiates or maintains the operation (and may be changed by it) and at least one passive part that is changed by the operation. The change may be to the location or other properties of a part, or it may transform it into another kind of part;
· mechanisms may involve multiple levels of organization;
· operations can be organized simply by temporal sequence, but those in biological mechanisms tend to exhibit more complex forms of organization;
· mechanisms can be dynamic and can change both ontogenetically and phylogenetically. [pp. 26-27]
Mechanisms explain phenomena [p. 27] by breaking them down into component parts and component operations (illustrated by the example of the pumping of blood by the heart, p. 31). Another distinctive feature of cell biology consists in the fact that biological systems involve a cohesive organization and orchestrated functioning [pp. 32-33]. Mechanistic thinking is at once ontic and epistemic [p. 33]. It proceeds principally along two lines, either linguistic description by means of narratives or pictorial description by means of diagrams [p. 34]. The levels of organization and reduction behave rather differently in cell biology than one is accustomed to surmise in the dominant philosophy of science [p. 40ff]. Bechtel traces the route taken by scientific reflection on the question from the Cartesian to the biological [pp. 44-53], by way of Claude Bernard (1865). The final topic Bechtel takes up in this finely written chapter is that of the discovery and testing of mechanisms by identifying working parts and component operations (structural/functional), the localization of operations in respective parts and lastly, the testing of models [pp. 54-63].
Chapter three, entitled ‘The locus of cell mechanisms between cytology and biochemistry’, is chock full of specific information going back to the nineteenth century and helpful for someone who came to maturity in the twenty-first century (knowing everything we now know) mentally to reconstruct what the field was like as of the early 1940’s. The other aspect, aside from what was known at the time, is what it was possible to investigate with the techniques then available. Thus, chapter four reviews the new instruments that became available during the period in question, such as the ultracentrifuge (for cell fractionation) and the electron microscope. Then, chapter five – ‘Entering terra incognita’ – shows how the new instrumentation began to revolutionize the field during the 1940’s. The historical core of Bechtel’s book in chapter six describes in fair detail the new knowledge arrived at by 1970, i.e., a treatment of the identification of the function of and of some actual mechanisms behind the mitochondrion, the endoplasmic reticulum, the ribosome, the Golgi apparatus and the lysosome. Chapter seven tells the story of how the new field of cell biology established its institutional identity through founding of journals and professional societies.
Four stars. It is nice that Bechtel does not stay overly abstract as often happens in discussions in philosophy of science, but backs up the theory in chapter two with a plethora of specific examples. Indeed, it is always exciting to see how people figured things out: we’re used to having everything spoon fed to us in our curriculum. Another amazing story Bechtel doesn’t relate would be that of how the genetic code was unraveled during 1950’s to 1960’s following Watson and Crick’s discovery in 1953 of the double helix structure of DNA. Bechtel emphasizes the role of technology in promoting radical advances in instrumentation over the period [pp. 118-189].
What remains for us today? We are, after all, in possession by now of a high-level overview of how most organelles function, but the omics revolution holds out the promise that one could elaborate in more detail on how the subcellular level interacts with cellular processes. If so, one might reduce the staggering complexity found everywhere in cell biology to conceptual order and thereby win insight into the operation of the higher levels. Then, as a final desideratum, proceed to the integration of cell biology with organismic biology and evolutionary developmental biology: for instance, what is the mechanism of memory formation and the like?
This is all well and good, if one be only a physicist. The great successes of modern physics however, not least in atomic physics after the advent of the quantum mechanics, encourage everyone to suppose that all natural phenomena ought to explicable in reductionistic terms, that is to say, mechanically. Meanwhile, after the second world war, the discipline of cell biology underwent a revolution propelled by advances in instrumentation made possible by the application of quantum physics to technology. The noted philosopher of science William Bechtel tells the story of these discoveries admirably in his Discovering Cell Mechanisms: The Creation of Modern Cell Biology (Cambridge Studies in Philosophy and Biology, originally published in 2006). The author figures as part of a small band of scholars who since the 1990’s have reconceived our vision of the nature of scientific inquiry, based on inspiration from biology as their model. Previously, received views in the philosophy of science had been dominated by physics, from the Vienna Circle to Hempel and Salmon – what scarcely seems unusual, given the tremendous growth of physics itself during the first half of the twentieth century. Thus, philosophy of science pursued in this mold tends to center on the questions of the status of determinism and reduction.
Why these are not so relevant in cell biology: as Aristotle stresses in his organon, the method it is desirable to follow in a given field ought to be appropriate to the subject matter. Nothing could be worse than to judge a claim to knowledge by an alien standard. For in fact systems characterized by the concurrence of very many relevant degrees of freedom confront us with a phenomenon sui generis, pace Dirac’s influential dicta to the effect that chemistry has henceforward been reduced to a branch of quantum physics:
The fundamental laws necessary for the mathematical treatment of a large part of physics and the whole of chemistry are thus completely known, and the difficulty lies only in the fact that application of these laws leads to equations that are too complex to be solved. [Quantum mechanics of many-electron systems, Proceedings of the Royal Society of London 73A, 714-733 (1929)]
The great systematician Ernst Mayr underscores in his Toward a New Philosophy of Biology: Observations of an Evolutionist (Harvard University Press, 1988) the marks that constitute biology as an autonomous scientific discipline: the exceptional complexity of living systems, their organization into populations, their possession of a genetic program, the precedence of a comparative method over the experimental, the relevance of high-level concepts that cannot readily be reduced to low-level terms (such a meiosis in cell reproduction), the different status of general laws and theories and lastly, the presence of adaptedness and teleology (or function, if one prefer) [pp. 8-23]. In view of these points, one could counter Dirac by saying that he might be right about chemistry, but certainly not about biology.
Typical of biology is that, in place of exact calculation and formulaic laws, it revolves largely around qualitative comprehension. Not that quantitative measurements are irrelevant; rather they play a different and more auxiliary role: to inform insight by fitting into a perceivable pattern rarely subject to precise prediction as part of a mathematical formalism. Natural laws, such as they may occur in biology, constitute generalizations often admitting of exceptions, expressed through natural language instead of through an analytical formula. Therefore, one has good antecedent grounds to expect that the contours of a philosophy of science drawing principally on biology rather than on physics ought to look very different.
The role of mechanism in particular is the crux. Why? Bechtel:
The science of cell biology is very different from the textbook image of science, including that advanced in traditional philosophy of science. That picture, grounded on some of the great successes of the scientific revolution and subsequent developments in some areas of physics, emphasizes bold unifying generalization – the laws of nature. Newton’s laws of motion promised to explain all motion, both terrestrial and celestial. The laws of thermodynamics and electromagnetism are similarly broad in their sweep. In biology, Darwin’s insight that evolution by natural selection occurs when there is heritable variation in fitness has provided a similarly powerful unifying generalization. However, most areas of biology – including cell biology – do not fit into this picture. Instead of unifying generalizations, cell biology offers detailed accounts of complex mechanisms in which different component parts perform specific operations, which are organized and orchestrated so that a given cell type can accomplish the functions essential for its life. Not elegant generalizations, but exquisitely detailed accounts of mechanisms, are the products. This difference in product has broad implications for our overall understanding of science, including the challenges of generating evidence, advancing new hypotheses and theories, and evaluating and revising them. [p. 2]
Why does cell biology count as a new discipline, beginning in the 1940’s and having attained this status by the late 1960’s?
The investigators who created cell biology were strongly committed to inquiry that related knowledge of the parts of the cell (organelles) and the chemical operations that took place in those parts. The methodologies that had been so successful in the early decades of biochemistry involved extracting the responsible enzymes and substrates from cells and studying reactions that did not depend on the specifics of cell structure. So for many biochemists, cells were unimportant. A number of cytologists, on the other hand, were eager to relate cell parts to chemical operations, but for the most part they lacked the tools to make the connections. Thus, despite the focus on cell structure and function by cytology and biochemistry...in 1940 there remained a terra incognita between these two fields. [p. 14]
Bechtel’s other major concern centers on what it took to get there:
The new research techniques pose both an engineering and an epistemic challenge. As in prototypical engineering tasks, in order to use the ultracentrifuge or the electron microscope, researchers had to figure out ways to accomplish new tasks – for example, to release the contents of cells from the cell membrane without disrupting internal structures and to stain cell components so that they would differentially diffract electrons. Engineering tasks like these give rise to the epistemic challenge of showing that the results reflect the phenomenon of interest and are not artifactual. [p. 15]
The theoretical chapter two starts out with historical conceptions of mechanism, paying special attention to Descartes, Boyle, Newton [p. 20ff]. The conception of mechanism current in the twentieth century draws on Hume and the logical empiricists. As of the time of Bechtel’s training, an influential voice on the topic of mechanism was the philosopher of science Wesley Salmon, whose conception goes beyond that of the seventeenth century. Bechtel discusses why [p. 24ff]. After this historical review, Bechtel’s carefully wrought definition of his terms reads like a series of patent claims:
A mechanism is a structure performing a function in virtue of its component parts, component operations and their organization. The orchestrated functioning of the mechanism is responsible for one or more phenomena.
Moreover:
· the component parts of the mechanism are those that figure in producing a phenomenon of interest;
· each component operation involves at least one component part. Typically there is an active part that initiates or maintains the operation (and may be changed by it) and at least one passive part that is changed by the operation. The change may be to the location or other properties of a part, or it may transform it into another kind of part;
· mechanisms may involve multiple levels of organization;
· operations can be organized simply by temporal sequence, but those in biological mechanisms tend to exhibit more complex forms of organization;
· mechanisms can be dynamic and can change both ontogenetically and phylogenetically. [pp. 26-27]
Mechanisms explain phenomena [p. 27] by breaking them down into component parts and component operations (illustrated by the example of the pumping of blood by the heart, p. 31). Another distinctive feature of cell biology consists in the fact that biological systems involve a cohesive organization and orchestrated functioning [pp. 32-33]. Mechanistic thinking is at once ontic and epistemic [p. 33]. It proceeds principally along two lines, either linguistic description by means of narratives or pictorial description by means of diagrams [p. 34]. The levels of organization and reduction behave rather differently in cell biology than one is accustomed to surmise in the dominant philosophy of science [p. 40ff]. Bechtel traces the route taken by scientific reflection on the question from the Cartesian to the biological [pp. 44-53], by way of Claude Bernard (1865). The final topic Bechtel takes up in this finely written chapter is that of the discovery and testing of mechanisms by identifying working parts and component operations (structural/functional), the localization of operations in respective parts and lastly, the testing of models [pp. 54-63].
Chapter three, entitled ‘The locus of cell mechanisms between cytology and biochemistry’, is chock full of specific information going back to the nineteenth century and helpful for someone who came to maturity in the twenty-first century (knowing everything we now know) mentally to reconstruct what the field was like as of the early 1940’s. The other aspect, aside from what was known at the time, is what it was possible to investigate with the techniques then available. Thus, chapter four reviews the new instruments that became available during the period in question, such as the ultracentrifuge (for cell fractionation) and the electron microscope. Then, chapter five – ‘Entering terra incognita’ – shows how the new instrumentation began to revolutionize the field during the 1940’s. The historical core of Bechtel’s book in chapter six describes in fair detail the new knowledge arrived at by 1970, i.e., a treatment of the identification of the function of and of some actual mechanisms behind the mitochondrion, the endoplasmic reticulum, the ribosome, the Golgi apparatus and the lysosome. Chapter seven tells the story of how the new field of cell biology established its institutional identity through founding of journals and professional societies.
Four stars. It is nice that Bechtel does not stay overly abstract as often happens in discussions in philosophy of science, but backs up the theory in chapter two with a plethora of specific examples. Indeed, it is always exciting to see how people figured things out: we’re used to having everything spoon fed to us in our curriculum. Another amazing story Bechtel doesn’t relate would be that of how the genetic code was unraveled during 1950’s to 1960’s following Watson and Crick’s discovery in 1953 of the double helix structure of DNA. Bechtel emphasizes the role of technology in promoting radical advances in instrumentation over the period [pp. 118-189].
What remains for us today? We are, after all, in possession by now of a high-level overview of how most organelles function, but the omics revolution holds out the promise that one could elaborate in more detail on how the subcellular level interacts with cellular processes. If so, one might reduce the staggering complexity found everywhere in cell biology to conceptual order and thereby win insight into the operation of the higher levels. Then, as a final desideratum, proceed to the integration of cell biology with organismic biology and evolutionary developmental biology: for instance, what is the mechanism of memory formation and the like?
Displaying 1 of 1 review