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The ovary of Eve: Egg and sperm and preformation
The ‘lkuth of Science: Physical Theories and Reality by R.G. Newton Harvard University Press, 1997. f17.95 hardback (viii + 260 pages) ISBN 0 674 91092 3 Scientific knowledge is abstract (in the case of physics particularly), and linked only very indirectly to the world we perceive with the senses. To what extent is science concerned with a truth independent of the activities of scientists, and to what extent is it merely a ‘social construction’, consisting of the activities of a particular culture? Such questions are the fundamental concern of this book, largely driven by disquiet at the claims of sociologists who have advocated the social construction point of view. Unfortunately (it seems to me), the author is neither enough of a philosopher nor enough of a sociologist to appreciate the issues fully, so that the book becomes rather of the nature of an apologia for science (but an interesting and instructive apologia nevertheless). What is it about scientific ‘truths’, over and above social processes, that entitles us to consider them as true? Newton discards as too simple-minded the idea that scientific assertions are simply ‘assertions of how things are’, so an alternative is required. His alternative is the coherence or overall consistency of a large and complex body of scientific knowledge. As an illustration of this coherence (exemplified by the fact of the non-existence of an engine that runs without the input of energy) he asserts that ‘when a well-corroborated theory implies that a phenomenon will never occur, it will, indeed, not happen’. The problem with this particular line is that the history of science contains a number of examples of laws that appeared at one time to be universally obeyed but which later were found to have exceptions. All of chemistry appeared to confirm the law that elements could not be transmuted, while the physics of the past seemed to imply that space and time were absolute. The moral to be drawn is that no matter how coherent a scientific system may be, there is no guarantee that facts that are inconsistent with it will not emerge in the future. In the end, Newton acknowledges this, and shifts to the idea that science, ‘Kuhn notwithstanding’, makes progress, and approaches the truth ever more closely over the course of time. The reference to Kuhn is one to a statement of his that science does not move towards anything such as truth, but simply evolves. Attacking this position, the author quotes Shimony, who uses a supposed analogy between deciphering of a coded text and the problem of understanding nature to argue that there could not be progress in science without there being some unambiguous truth that this progress was heading for. But the analogy is unconvincing; it is like saying if a society continually makes progress then there must be some unique
Copyright
0
1998
Elsevier
Science
Ltd. All right
reserved.
perfect society that is the limit of this progress (or more mathematically, that if we have an ascending sequence of integers there is some integer that is the limit of that sequence). The whole notion of scientific truth is so troublesome that it seems much better to avoid it, and to discuss the nature of scientific progress instead. What of the idea, which Newton seems to detest, that science is an ‘endeavour to construct reality’? One cannot argue with the idea itself; the ob,jection is to the idea that that is all there is to science: Newton wants there to be something independent of the scientist that underlies the outcome of such endeavours. But it is not clear that relativism in itself excludes that possibility. If I stand on a mountain, I see things that have an existence independent of myself, and yet what it is possible for me to see depends on where I stand. Some of Newton’s criticism of Pickering’s glosses on relativism I can accept. Nevertheless, Pickering arguably is right in contexts such as string theory, where different versions of theories that claim to be descriptions of reality come and go like fashions. Here, objectivity fights against the human desire to profit from the latest ways of thinking, as (to quote Pickering) scientists attempt to do the thing that will bring them as individuals the greatest gain. A better book could have been written if the central theme had been not scientific truth but scientific progress, and the question of what it is about science and its methods that allows it (sometimes) to make clear progress by resolving inconsistencies in a widely acceptable manner. What is important in this context, as is made clear, is that the methods of science (such as making experiment rather than theory the ultimate arbiter of the truth) leave less room for personal opinion to determine what is correct than may be the case in some other disciplines (though some scientists seem endemically given to underestimating the degree of rigour of other disciplines, particularly in the humanities, and to elevating science to a status of uniqueness that it perhaps does not deserve). As a final point that 1 feel is instructive, Newton seems to think in the case of parapsychology that its ‘incoherence with the rest of accepted science’ is a good reason for ignoring the experimental evidence. As has already been explained, it seems not, in the light of the history of science, to be a very good reason. But the fact that scientists are inclined nonetheless to see it as a good reason seems to demand a sociological explanation (e.g. in terms of taboo). The saga of parapsychology refutes the suggestion that ‘science is objective to the extent it avoids bias because the public character of science produces a balance with that effect.’ The public character of science can help foster a view consistent with revealed reality, but can sometimes instead produce blinkers that help inhibit such a state of affairs.
0160-9327/98/$19.00
I do not think that Newton has made the case that he hoped to have made, but the book nevertheless makes very interesting reading for its analyses of how science works. It also provides for the scientist particularly a useful introduction to relativist ideas. B.D. Josephson
The Ovary of Eve: Egg and Sperm and Preformation by C. Pinto-Correiu University of Chicago Press, 1997. $29.95 hardback (xxiii + 396 pages) ISBN 0 226 66952 1 This is a very strange book indeed; it will delight those, like me, who enjoy excursions into the strange ways of antique or foreign minds, looking at problems we have seen and worried over, but from wholly new perspectives. It will infuriate those, like me, who want the problems to be, if not answered, at least pigeon-holed so we can forget them. But those who have not seen the problems will be bored and angered in equal measure: such excursions into obviously wrong by-ways, such obvious misrepresentations of the truths we have finally found and which make modern science such a glorious edifice, are simply a waste of laboratory time. Not for them this book, because it needs an appreciation of how wrong our most cherished theories might look - doubtless will look - to a specialist in whatever succeeds science in several hundred years’ time. The central issue is the delusion that there is a rule which we might call ‘The Law of Conservation of Complexity’. According to this (spurious) Law, simple processes and antecedents produce simple products, complex processes and antecedents produce complicated products. Most people did, and do, believe this, so it is not reasonable that a complicated being like you arose from a simple-looking egg. In theology-informed thinking, God had to have pre-formed you in your mother’s eggs - or your father’s ‘seed’ - and of necessity within you arc all your descendants until the Day of Judgement. So, within the ovary of Eve were all her progeny pre-formed (including you and me), awaiting only the exposure of copulation, then birth, to usher each generation into the world. The modern preformationist version does not suppose that there is such literal preformation, but that the DNA-information in your chromosomes - and in your egg - sits there in all its glorious complexity, a blueprint as you develop. According to this view, you are your DNA made flesh, complexity made complicated. However, in contrast to this spurious rule, modern embryologists and complexity theorists agree on a very diRerent model. Complexity is not a ‘conserved quantity’, like energy or mass; it genuinely does increase during development
Endeavour
Vol. 22(2) 1998
83
(for more discussion of this point, see books by Stuart Kauffman, by me and Ian Stewart, by Steven Pinker, and many more). One growing feather, by any measure of complexity, is much more complicated than the patch of cells on the yolk from which arose the whole chicken! These issues puzzled the early anatomists greatly; it was clear that either sex could contribute characters to their joint progeny, and this did not sit well with either sperm preformationism or ovism. Nor did ‘monsters’, for God would have had to encapsulate them in their thousands in Eve’s ovary and their appearance would have to serve God’s aims at the birth time - if God had made so detailed a history, free will was a very difficult contradiction. These were clever people, they saw the problems, and Clara Pinto-Correia makes this very clear to us. Different historical threads wove in and out of the philosophical discussions; sometimes, as with Haller, his philosophy changed and he adopted different positions in succession. Spallanzani, in contrast, was an ovist but is usually perceived by us as a spermist because of his experiments with toad barrier-contraception. Hartsoeker, whose drawing of the little man in the egg is the famous one, probably drew it as a cartoon, critical of spermist beliefs (Schrodinger probably did the same with the ‘cat in a box’ story, which has also been used mostly for the opposite of his intention). And calling the little man a ‘homunculus’ probably started in this century, not in Enlightened times. An alternative concept, epigenesis, was taken from Aristotle: different ‘fluids’ contributed differently, according to environmental differences (but the rule still held . ..). various mutations of this concept allowed interaction between male and female contributions to make a more complicated entity, the germ, which could develop complexity and showed characters from both parents. But this did not resolve all the problems which had beset the early observers, of spermatozoa in their hundreds of millions, or of developing eggs. The idea that one sperm was involved was not common: like the liquids of the female tract (commonly blood/menstruum, but also female ejaculate, depending perhaps on the sexual experiences of the male philosophers), the semen was commonly supposed all to be involved in the ‘moulding’ of the embryo. As they saw it, if only one spermatozoon was used to invigorate the egg, God’s economy required function for all the rest; and this led to ideas which included the myriads of spermatozoa taking off into the atmosphere to promote growth in other animals and plants. Observations of chicken eggs developing showed overt increase in complexity, so that naive ovism (the chicken was in there complete-but-tiny) never worked; but the source of the progressive increase of structure was pursued with as much fervour as in the modern molecular-biology lab (‘Which gene accounts for
84
Endeavour
Vol. 22(2) 1998
the structure of the hand . . .?‘). Regeneration of limbs by crustaceans and amphibians was puzzling, interesting, like parthenogenesis in aphids. But Trembley’s demonstration of the regeneration of whole Hydras was a bombshell. The Ovary of Eve lays out all this froth of dissent, concern, fervour and experiment caught up in the incomprehension of increase of complexity without divine intervention. The author is too soft on astrology for my taste, and there are a few gross biological errors -Hydra is called a unicell, for example. She shows us that, like today’s child (‘But where does it come from . . .?‘) or today’s adult (‘Yes, but what came before the Big Bang . . .?‘), they’ve missed the point - or at least, that they’ve missed our point. There are two intertwined deep messages in this book: that they were as clever and inventive and critical as we are, and as critical of their assumptions; and that these same questions are still with us, imposed on our assumptions and, usually, not dealt with in as charming a manner. ‘The fat lady cannot sing yet’ says Prof. Pinto-Correia: we do not yet have final, true answers. I am surprised she expects us ever to get there. I think that fat lady will never sing. Conservation of complexity will be forgotten. Jack Cohen
Foundation of Biophilosophy by M. Mahner and M. Bunge Springer-Verlag, 1997. DM84.00 hardback (xviii + 423 pages) ISBN 3 540 61838 4 Dobzhansky’s dictum that ‘nothing makes sense in biology except in the context of evolutionary theory’ has been taken very very seriously by most of the major works in the short history of the philosophy of biology. Landmarks such as Sober’s The Nature of Selection (1984) have certainly helped to solidify the view that the philosophy of biology has been largely synonymous with the philosophy of evolutionary theory. Indeed, many other major contemporary contributors in the philosophy of biology, like Brandon and Kitcher, have taken evolutionary theory to be its hard core, its theoretical holy grail. This in itself is not a problem, since evolutionary theory is the most general and pervasive of all biological theories. However, by concentrating on evolutionary theory, other aspects of biology such as the nature of life, ecology, and psychobiology have been left at the periphery of the philosophy of biology. Perhaps now that the philosophy of biology has matured into a full-fledged discipline, it can expand beyond its evolutionary core to consider these otherwise orphaned topics. Mahner and Bunge’s Foundations of Biophilosophy makes strides in this direction by steadfastly rejecting the philosophy
Copyright
0 1998 Elsevier
of biology’s previous commitment to evolutionary theory. The authors of this lengthy volume attempt to revamp the philosophy of biology by laying the conceptual foundation for the philosophical investigation of all aspects of biology without special emphasis on evolutionary biology, or any other particular aspect of biology. They begin with a 134-page treatise on general philosophy of science, in which they articulate the ontological, semantic and epistemological foundations of science. It is evident throughout that the authors believe themselves to be writing the as-yet-unwritten foundational work in the philosophy of biology. Their approach, though currently unfashionable in the philosophy of science, is unabashedly axiomatic-deductive. So, gone is the idea that for a philosophy of biology to exist as a unique discipline, the philosophy must itself be unique. That is, biophilosophy is neither a product of philosophers’ special interest in biology in general, nor evolutionary theory in particular. Instead, it is the application of a fundamental philosophy of science to topics in biology. Mahner and Bunge’s basic philosophy of science couples a realist ontology with an emergentist metaphysics. Among the various positions they endorse, only material causation is considered to merit scientific interest, and with respect to the language of science, they maintain a sharp separation between real properties and the predicates used in theories to describe them. This distinction is key to their epistemology, where there is a hard division between theories and the objects described by theories. Accordingly, truth, on their account, must be divided along linguistic lines, yielding a distinction between truths of reason and truths of fact. However, while humans create theories, we are assured that the language of science reliably describes reality because humans are themselves ultimately natural, biophysical products of evolution. These foundational considerations are then applied to a variety of topics in biology including, by order of the chapters: Life, Psychobiology, Systematics, Ecology, Developmental Biology, Evolutionary Theory and Teleology. Each receives systematic treatment in light of the fundamental principles developed in the first quarter of the book, but the results are not particularly illuminating. Much of the analysis depends upon the plausibility of the translation of the relevant biology into principles, definitions and symbolic notation. While this might assure the conformity of the biological principles to the author’s a priori philosophical convictions, it does so at the cost of paring the biological detail down to a manageable minimum. As a consequence, Foundations of Biophilosophy does not engage very much actual biology. More importantly, because of the limited scope of their proofs, their conclusions tend to be general, if not trivial in some cases. Whereas many philosophers of biology have been preoccupied with evolutionary
Science
Ltd. All right reserved.
0160-9327/98/$19.00.
Copyright
0
1998
Elsevier
Science
Ltd. All right
reserved.
perfect society that is the limit of this progress (or more mathematically, that if we have an ascending sequence of integers there is some integer that is the limit of that sequence). The whole notion of scientific truth is so troublesome that it seems much better to avoid it, and to discuss the nature of scientific progress instead. What of the idea, which Newton seems to detest, that science is an ‘endeavour to construct reality’? One cannot argue with the idea itself; the ob,jection is to the idea that that is all there is to science: Newton wants there to be something independent of the scientist that underlies the outcome of such endeavours. But it is not clear that relativism in itself excludes that possibility. If I stand on a mountain, I see things that have an existence independent of myself, and yet what it is possible for me to see depends on where I stand. Some of Newton’s criticism of Pickering’s glosses on relativism I can accept. Nevertheless, Pickering arguably is right in contexts such as string theory, where different versions of theories that claim to be descriptions of reality come and go like fashions. Here, objectivity fights against the human desire to profit from the latest ways of thinking, as (to quote Pickering) scientists attempt to do the thing that will bring them as individuals the greatest gain. A better book could have been written if the central theme had been not scientific truth but scientific progress, and the question of what it is about science and its methods that allows it (sometimes) to make clear progress by resolving inconsistencies in a widely acceptable manner. What is important in this context, as is made clear, is that the methods of science (such as making experiment rather than theory the ultimate arbiter of the truth) leave less room for personal opinion to determine what is correct than may be the case in some other disciplines (though some scientists seem endemically given to underestimating the degree of rigour of other disciplines, particularly in the humanities, and to elevating science to a status of uniqueness that it perhaps does not deserve). As a final point that 1 feel is instructive, Newton seems to think in the case of parapsychology that its ‘incoherence with the rest of accepted science’ is a good reason for ignoring the experimental evidence. As has already been explained, it seems not, in the light of the history of science, to be a very good reason. But the fact that scientists are inclined nonetheless to see it as a good reason seems to demand a sociological explanation (e.g. in terms of taboo). The saga of parapsychology refutes the suggestion that ‘science is objective to the extent it avoids bias because the public character of science produces a balance with that effect.’ The public character of science can help foster a view consistent with revealed reality, but can sometimes instead produce blinkers that help inhibit such a state of affairs.
0160-9327/98/$19.00
I do not think that Newton has made the case that he hoped to have made, but the book nevertheless makes very interesting reading for its analyses of how science works. It also provides for the scientist particularly a useful introduction to relativist ideas. B.D. Josephson
The Ovary of Eve: Egg and Sperm and Preformation by C. Pinto-Correiu University of Chicago Press, 1997. $29.95 hardback (xxiii + 396 pages) ISBN 0 226 66952 1 This is a very strange book indeed; it will delight those, like me, who enjoy excursions into the strange ways of antique or foreign minds, looking at problems we have seen and worried over, but from wholly new perspectives. It will infuriate those, like me, who want the problems to be, if not answered, at least pigeon-holed so we can forget them. But those who have not seen the problems will be bored and angered in equal measure: such excursions into obviously wrong by-ways, such obvious misrepresentations of the truths we have finally found and which make modern science such a glorious edifice, are simply a waste of laboratory time. Not for them this book, because it needs an appreciation of how wrong our most cherished theories might look - doubtless will look - to a specialist in whatever succeeds science in several hundred years’ time. The central issue is the delusion that there is a rule which we might call ‘The Law of Conservation of Complexity’. According to this (spurious) Law, simple processes and antecedents produce simple products, complex processes and antecedents produce complicated products. Most people did, and do, believe this, so it is not reasonable that a complicated being like you arose from a simple-looking egg. In theology-informed thinking, God had to have pre-formed you in your mother’s eggs - or your father’s ‘seed’ - and of necessity within you arc all your descendants until the Day of Judgement. So, within the ovary of Eve were all her progeny pre-formed (including you and me), awaiting only the exposure of copulation, then birth, to usher each generation into the world. The modern preformationist version does not suppose that there is such literal preformation, but that the DNA-information in your chromosomes - and in your egg - sits there in all its glorious complexity, a blueprint as you develop. According to this view, you are your DNA made flesh, complexity made complicated. However, in contrast to this spurious rule, modern embryologists and complexity theorists agree on a very diRerent model. Complexity is not a ‘conserved quantity’, like energy or mass; it genuinely does increase during development
Endeavour
Vol. 22(2) 1998
83
(for more discussion of this point, see books by Stuart Kauffman, by me and Ian Stewart, by Steven Pinker, and many more). One growing feather, by any measure of complexity, is much more complicated than the patch of cells on the yolk from which arose the whole chicken! These issues puzzled the early anatomists greatly; it was clear that either sex could contribute characters to their joint progeny, and this did not sit well with either sperm preformationism or ovism. Nor did ‘monsters’, for God would have had to encapsulate them in their thousands in Eve’s ovary and their appearance would have to serve God’s aims at the birth time - if God had made so detailed a history, free will was a very difficult contradiction. These were clever people, they saw the problems, and Clara Pinto-Correia makes this very clear to us. Different historical threads wove in and out of the philosophical discussions; sometimes, as with Haller, his philosophy changed and he adopted different positions in succession. Spallanzani, in contrast, was an ovist but is usually perceived by us as a spermist because of his experiments with toad barrier-contraception. Hartsoeker, whose drawing of the little man in the egg is the famous one, probably drew it as a cartoon, critical of spermist beliefs (Schrodinger probably did the same with the ‘cat in a box’ story, which has also been used mostly for the opposite of his intention). And calling the little man a ‘homunculus’ probably started in this century, not in Enlightened times. An alternative concept, epigenesis, was taken from Aristotle: different ‘fluids’ contributed differently, according to environmental differences (but the rule still held . ..). various mutations of this concept allowed interaction between male and female contributions to make a more complicated entity, the germ, which could develop complexity and showed characters from both parents. But this did not resolve all the problems which had beset the early observers, of spermatozoa in their hundreds of millions, or of developing eggs. The idea that one sperm was involved was not common: like the liquids of the female tract (commonly blood/menstruum, but also female ejaculate, depending perhaps on the sexual experiences of the male philosophers), the semen was commonly supposed all to be involved in the ‘moulding’ of the embryo. As they saw it, if only one spermatozoon was used to invigorate the egg, God’s economy required function for all the rest; and this led to ideas which included the myriads of spermatozoa taking off into the atmosphere to promote growth in other animals and plants. Observations of chicken eggs developing showed overt increase in complexity, so that naive ovism (the chicken was in there complete-but-tiny) never worked; but the source of the progressive increase of structure was pursued with as much fervour as in the modern molecular-biology lab (‘Which gene accounts for
84
Endeavour
Vol. 22(2) 1998
the structure of the hand . . .?‘). Regeneration of limbs by crustaceans and amphibians was puzzling, interesting, like parthenogenesis in aphids. But Trembley’s demonstration of the regeneration of whole Hydras was a bombshell. The Ovary of Eve lays out all this froth of dissent, concern, fervour and experiment caught up in the incomprehension of increase of complexity without divine intervention. The author is too soft on astrology for my taste, and there are a few gross biological errors -Hydra is called a unicell, for example. She shows us that, like today’s child (‘But where does it come from . . .?‘) or today’s adult (‘Yes, but what came before the Big Bang . . .?‘), they’ve missed the point - or at least, that they’ve missed our point. There are two intertwined deep messages in this book: that they were as clever and inventive and critical as we are, and as critical of their assumptions; and that these same questions are still with us, imposed on our assumptions and, usually, not dealt with in as charming a manner. ‘The fat lady cannot sing yet’ says Prof. Pinto-Correia: we do not yet have final, true answers. I am surprised she expects us ever to get there. I think that fat lady will never sing. Conservation of complexity will be forgotten. Jack Cohen
Foundation of Biophilosophy by M. Mahner and M. Bunge Springer-Verlag, 1997. DM84.00 hardback (xviii + 423 pages) ISBN 3 540 61838 4 Dobzhansky’s dictum that ‘nothing makes sense in biology except in the context of evolutionary theory’ has been taken very very seriously by most of the major works in the short history of the philosophy of biology. Landmarks such as Sober’s The Nature of Selection (1984) have certainly helped to solidify the view that the philosophy of biology has been largely synonymous with the philosophy of evolutionary theory. Indeed, many other major contemporary contributors in the philosophy of biology, like Brandon and Kitcher, have taken evolutionary theory to be its hard core, its theoretical holy grail. This in itself is not a problem, since evolutionary theory is the most general and pervasive of all biological theories. However, by concentrating on evolutionary theory, other aspects of biology such as the nature of life, ecology, and psychobiology have been left at the periphery of the philosophy of biology. Perhaps now that the philosophy of biology has matured into a full-fledged discipline, it can expand beyond its evolutionary core to consider these otherwise orphaned topics. Mahner and Bunge’s Foundations of Biophilosophy makes strides in this direction by steadfastly rejecting the philosophy
Copyright
0 1998 Elsevier
of biology’s previous commitment to evolutionary theory. The authors of this lengthy volume attempt to revamp the philosophy of biology by laying the conceptual foundation for the philosophical investigation of all aspects of biology without special emphasis on evolutionary biology, or any other particular aspect of biology. They begin with a 134-page treatise on general philosophy of science, in which they articulate the ontological, semantic and epistemological foundations of science. It is evident throughout that the authors believe themselves to be writing the as-yet-unwritten foundational work in the philosophy of biology. Their approach, though currently unfashionable in the philosophy of science, is unabashedly axiomatic-deductive. So, gone is the idea that for a philosophy of biology to exist as a unique discipline, the philosophy must itself be unique. That is, biophilosophy is neither a product of philosophers’ special interest in biology in general, nor evolutionary theory in particular. Instead, it is the application of a fundamental philosophy of science to topics in biology. Mahner and Bunge’s basic philosophy of science couples a realist ontology with an emergentist metaphysics. Among the various positions they endorse, only material causation is considered to merit scientific interest, and with respect to the language of science, they maintain a sharp separation between real properties and the predicates used in theories to describe them. This distinction is key to their epistemology, where there is a hard division between theories and the objects described by theories. Accordingly, truth, on their account, must be divided along linguistic lines, yielding a distinction between truths of reason and truths of fact. However, while humans create theories, we are assured that the language of science reliably describes reality because humans are themselves ultimately natural, biophysical products of evolution. These foundational considerations are then applied to a variety of topics in biology including, by order of the chapters: Life, Psychobiology, Systematics, Ecology, Developmental Biology, Evolutionary Theory and Teleology. Each receives systematic treatment in light of the fundamental principles developed in the first quarter of the book, but the results are not particularly illuminating. Much of the analysis depends upon the plausibility of the translation of the relevant biology into principles, definitions and symbolic notation. While this might assure the conformity of the biological principles to the author’s a priori philosophical convictions, it does so at the cost of paring the biological detail down to a manageable minimum. As a consequence, Foundations of Biophilosophy does not engage very much actual biology. More importantly, because of the limited scope of their proofs, their conclusions tend to be general, if not trivial in some cases. Whereas many philosophers of biology have been preoccupied with evolutionary
Science
Ltd. All right reserved.
0160-9327/98/$19.00.