A Search for the Certitude of Scientific Facts with Giambattista Vico and Karl Popper: The Importance of Integrative Physiology G. G. Pinter, Vera Pinter Perspectives in Biology and Medicine, Volume 35, Number 3, Spring 1992, pp. 436-442 (Article) Published by Johns Hopkins University Press DOI: https://doi.org/10.1353/pbm.1992.0024
For additional information about this article https://muse.jhu.edu/article/405805
Access provided at 5 Nov 2019 03:47 GMT from Miami University Libraries
A SEARCH FOR THE CERTITUDE OF SCIENTIFIC FACTS WITH GIAMBATTISTA VICO AND KARL POPPER: THE IMPORTANCE OF INTEGRATIVE PHYSIOLOGY G. G. PINTER* and VERA PINTERf
It is recorded of the Greek philosopher Cratylus that, having resolved
never to make a statement of whose truth he could not be certain, he was
in the end reduced simply to wagging his finger. —A. J. Ayer. [1]
Some years ago, a friend of ours [2] was lecturing on renal physiology to medical students at the University of Uppsala, when an impatient student, banging down his pencil on the bench, shouted: "Professor, don't give me all those theories, just give me the facts!" Our first physiology professor, G. Mansfeld [3], wrote in the preface of his book summing up 20 years of research: "A single fact is worth more than all the theories and hypotheses of the world."
Having spent several decades in teaching and research, we, too, have
searched for the certitude of facts in science. Our endeavor did not lead
to the success we have expected or, frankly, strongly hoped for. In teaching renal physiology, our experience was that we could not answer all questions raised by students with equal confidence. This was not so solely because in many regards we were ignorant. More often, the reason for our uncertainty was the nature of the question. When questions related to the "conceptual framework" of the subject—e.g., definitions such as clearance or free water, or models of the countercurrent mechanism of the urine concentration—our answers were certain and accu-
rate. But when the questions were aimed at the actual processes of how the kidney works, our answers were less definite and often more equivo*Department of Physiology, University of Maryland School of Medicine, SM, UMAB, 660 West Redwood Street, Baltimore, Maryland 21201, and King's College, London, England.
tWhipps Cross Hospital, Leytonestone, London, England. © 1992 by the University of Chicago. All rights reserved. 0031-5982/92-3503-0786$01.00
436
G. G. Pinter and Vera Pinter ¦ Integrative Physiology
cal: in some cases pertinent experimental results were not in full agree-
ment, in others the interpretation of the results differed, and in yet
other instances there were some other limitations to the certitude of the facts.
Are there facts known to us with certainty about nature? The question may be as old as Homo sapiens, and the oxymoron implied is, indeed, disconcerting. We do not pretend or hope to examine it from the begin-
ning, and our intrusion into epistemology is admittedly amateurish. Nevertheless, after inserting a few definitions of some relevant words, we will make an attempt to find an answer. We propose to seek guidance by the relevant thoughts of two philosophers whose ideas have made lasting impressions on us: Giambattista Vico and Karl Popper.
The American Heritage Dictionary defines both fact and truth in context of knowledge. "Fact: 1. something known with certainty, 2. something asserted as certain"; "Truth: 1. conformity to knowledge, fact, actuality, or logic." About knowledge, A.J. Ayer [1] wrote "the necessary and sufficient conditions for knowing that something is the case are first
that what one is said to know be true, secondly that one is sure ,of it,
and thirdly that one should have the right to be sure."
InDe antiquissima Italorum sapienta [4], published in 1710, Giambattista Vico wrote: "verum et factum reciprocantur, seu, . . . convertuntur." The meaning of this statement is, perhaps, best captured by Bertrand Russell [5]: "For Vico, the condition of knowing something is to have made it. The basic formulation of the principle is that we can only know what
we can do or make." Vico expressed this thought in several ways and in several contexts. Thus: "We demonstrate geometry because we make it: if we could demonstrate physical facts, we should be creating them" [6]. Again, "We demonstrate mathematics, because we create their truth"
[6]. "Verum ipsum factum," a succinct expression of Vico's assertion, has
been interpreted by Benedetto Croce [6] as follows: "The condition
under which a thing can be known is that the knower should have made
it, . . . the true is identical with the created." Croce [6] wrote also this: "Certitude ... is not science."
Vico thus explained our experience when we tried to answer the questions of our students, namely our experience of having been quite certain of man-made theories and concepts while lacking the same certitude about processes occurring in nature. But are Vico's ideas still valid? Has he been superseded by more modern epistemology? We turn to Karl Popper for further guidance.
Among Popper's contributions, two seem to be highly relevant to our question regarding certitude or facts in science. The first is his solution to the problem of inductive reasoning. The second is his recognition of a domain of human creations that he called "world 3." Let us attend
first to the problem of inductive reasoning.
Perspectives in Biology and Medicine, 35, 3 ¦ Spring 1992 | 437
David Hume [7] held that inductive reasoning is invalid' "even after the observation of the frequent conjunction of objects, we have no rea-
son to draw any inference concerning any object beyond those of which we have experience." Of this, Bertrand Russell [8] wrote: Hume's skepticism rests entirely upon his rejection of the principle of induction. ... If this principle, or any other from which it can be deduced, is true,
then the causal inferences which Hume rejects are valid, not indeed as giving
certainty, but as giving sufficient probability for practical purposes. If this principle is not true, every attempt to arrive at general scientific laws from particular observations is fallacious, and Hume's skepticism is inescapable for the empiricist. . . . What these arguments prove—and I do not think the proof can be controverted—is that induction is an independent logical principle, incapable of being inferred either from experience or from other logical principles, and that without this principle science is impossible.
Popper has been given credit for eliminating inductive reasoning
from scientific logic and for redefining the role of theory and hypothesis in the process. According to Popper [9], scientific investigation is, like many other human activities, in essence a form of problem solving: once a problem is identified, solution is sought by trial and error. In scientific research a hypothesis is formulated from which—by deductive reasoning—conclusions are drawn, and these conclusions are then
tested either by experiment or by matching them against known conclusions from other theories with the view of showing that the hypothesis is wrong, i.e., of falsifying it. Even if a hypothesis escapes early falsification by some number of tests of this type, it is not considered to be
verified, since it has to survive many similar tests still to come. When a hypothesis is found to be false, the next step is to modify it or to state a new hypothesis and go through a new cycle of testing the new hypothesis. The repetition of these cycles is infinite, and in the process the "verisimilitude" of the hypothesis with nature can increase. No inductive
reasoning is involved in this scheme; and testing of hypotheses is done with the intent of falsifying them and not of "confirming" or "verifying" them. Popper wrote [10]: "Every genuine test of a theory is an attempt to falsify it. ... A theory which is not refutable is not scientific. . . .
Some genuinely testable theories when found to be false are still upheld by their admirers for example by introducing ad hoc some auxiliary assumption or by re-interpreting the theory ad hoc in such a way that it escapes refutation. Such a procedure is always possible, but it rescues the theory from refutation only at a price of destroying, or at least lowering, its scienfitic status."
The process defined by Popper will not result in facts or positive certitude informing how things are in nature. While the verisimilitude with nature of set hypotheses may keep increasing, our knowledge will still remain encapsulated within changing and evolving hypotheses and 438 I G. G. Pinter and Vera Pinter ¦ Integrative Physiology
will continue to reside on this side of the boundary visualized by Vico, as theories and hypotheses are man-made. This, however, does not mean that our knowledge belongs to the world of subjective ideas. In addition to a world of objects (Popper's world 1), and a world of subjective ideas (his world 2), Popper [11] recognized a third domain to which belong mathematics, works of art, theories, etc., which, although created by human beings, have acquired independent existence from us (his world 3). The continuing quest for increasing the verisimilitude contained in the ever-changing hypotheses about nature belong to Popper's world 3.
Thus, we arrive at the conclusion that facts and positive certainty about nature elude us; instead we find a dynamic universe of science
that contains unfolding conjectures, hypotheses, and theories, and the wherewithal of observations, experimentation, and modelling, etc., that are the tools of this evolution. In this universe error is an organic part of the scientific process, as the intent to reduce it is the driving force of progress towards greater verisimilitude with nature. The demarcation
between science and non-science is whether a hypothesis is testable.
To us this view of science seems more self-consistent and more attrac-
tive than any other view we are familiar with. There are, of course, other opinions, and both Vico and Popper have opponents and detractors of their views. Vico has been said to repeat only the tenets of scholastic philosophers who held that since God created everything God knows everything. Croce [6] showed that Vico's contributions are much more significant and far-reaching than being just a derivative of scholastic philosophy. Popper's claim to have made inductive reasoning unnecessary in scientific logic has not been accepted by everybody, and Ayer [12] drew attention to the point that when a hypothesis is tested according to Popper's scheme, deductions from it are compared to deductions from
other hypotheses that also have an only limited time of survival. Without going into details, it seems that at this juncture Kuhn's [13] insight into potential changes of entire paradigms might complement Popper's
views.
With the simple-minded confidence of amateurs in the power and the limitations of science as we understand it, we should like to examine a
question of whether it is possible to accelerate the process of improving our hypotheses. Are there any shortcuts?
The past two decades in biological and medical research have seen a
new trend toward cellular, subcellular, and molecular dimensions, while
interest in research on organ systems has declined. It might seem conceivable that research on small consistent parts of the living systems should require simpler hypotheses that should be easier to test than on
integrated systems demanding complex hypotheses and more elaborate tests. Is there a ray of hope that here we might have a recipe for an Perspectives in Biology and Medicine, 35, 3 · Spring 1992
439
accelerated growth of the biological and medical sciences? The importance of this question is pointed up by the circumstance that there is a growing number of research workers who seem to believe that certainty
may be achievable in molecular biology. Research on isolated small building blocks of living organisms may result in a rapid accumulation of theories and hypotheses on these objects. However, we should consider that these small building blocks make up larger entities in an integrated fashion, and that these parts are coordinated by feedback loops in a synergistic and balanced organization. This integration of small parts makes it possible that large living
systems are capable of performing functions that cannot be derived by simply adding up the functions of the isolated small parts. An example from the field of renal physiology (to which we like to anchor ourselves) of these emerging qualities is the current status of the
hypotheses related to the mechanism of how the mammalian kidney produces urine that can be more concentrated or more dilute than the
blood plasma from which urine is ultimately made. This ability of the
kidney appeared relative late on the phylogenetic time scale in mammals and to some degree in birds. Current hypotheses attribute only an ancillary role in the urine concentrating and diluting process to specific sub-
cellular or molecular entities (such as the accumulation of osmolytes in cells and insertion of water permeable aggregates into the membrane of some tubular cells). The primary mechanism held responsible for the concentrating ability is that a section of the uriniferous tubules and accompanying blood vessels in the medulla of the kidney become folded in a particular U-shape. The cells constituting these tubules and blood vessels are not assumed to have unique qualities: their permeability and transport characteristics are assumed to be similar to those found else-
where in the kidney. The ability of carrying out the specific concentrating and diluting functions is attributed to the interacting arrangement between various parts of the U-shaped tubules, as well as to the same type of arrangement of blood vessels, and also to the interaction between these tubules and blood vessels—all these in a highly specific topography
[14, 15]. Clearly, in this case long-existing structures and functional
characteristics have been rearranged and integrated whereby a new
function could emerge. It is important to note here that the hypothesis injecting the new idea for the urine concentrating and diluting process was put forward after the potential significance of the entire structure of the U-tubes in the renal medulla was recognized and shown to be
capable of doing concentrating work in a model [14].
This example should remind us that complex systems abound in biology—systems that demand hypotheses that take into account the specific interactions between the constituent parts. We do not try to
deny the necessity and usefulness of studying subcellular and molecular 440 I G. G. Pinter and Vera Pinter ¦ Integrative Physiology
constituents of the living system. We assert, however, that if we intend to approach the problem of how organisms live, such study should derive its problems and targets from the integrated whole in order that essential internal coordinations not be forgotten. To proceed in the opposite direction, i.e., to try building up the integrated system from small constituents without a master plan, is an unnecessarily blind and difficult task, and claims to the contrary are, at best, mirages. Our unsophisticated excursion into epistemology as related to the
current focus of the biological and medical research provides some perspective to raise questions about current practices. The shift in focus and of support of research in these sciences from integrated physiology to molecular and subcellular aspects has been both substantial and longlasting. The effects of long duration of this shift can not be overlooked, since it involves not only the direction of research but also the education of young scientists. Even if we were to concede (an overly generous concession) that current research on subcellular constituents derived all
of its objectives from sources of integrated physiology, these sources are being replenished at the present time at an ever-diminishing rate. Eventually the trend of trying to build up and understand the living organism from small constituents without a blueprint of integrated physiology shall overwhelm us—if it has not started to do so already. If
no corrective action is taken, it is predictable that this trend shall grow quickly out of all bounds since, in this unhappy future, integrative physiology will be taught by teachers whose expertise will be in other fields, and who will keep only one step ahead of their students in reading a textbook that will not have been truly updated for many years or decades.
For all practical purposes, science seems to have unlimited power and potential. In its endeavor to understand the world, however, it also has
some limitations. Vico had the insight to define a limit to our knowledge,
and Popper has developed clear and specific guiding principles compatible with Vico's insight, concluding that falsehood can be rejected with certainty but that the truth about nature remains uncertain in the domain of the theories and hypotheses that have not as yet been falsified. It may be timely to remember the limitations of science when one branch of biological research appears to make implicit claims not only to offer numerous practical successes (which it can deliver), but also to possess
a unique access to certitude about nature (which should remain beyond its reach). REFERENCES
1.Ayer, A.J. The Problem of Knowledge. London: Penguin Books, 1990.
2.Ulfendahl, H. R. Personal communication.
Perspectives in Biology and Medicine, 35, 3 ¦ Spring 1992
441
3.Mansfeld, G. Die Hormone der Schilddruese and ihre Wirkungen. Basel: Benno Schwabe & Co., 1943.
4.Vico, G. B. De antiquissima Italorum sapientia ex linguae Latinae originibus eruenda. Neapoli: Mosca, 1710. 5.Russell, B. The Wisdom of the West. London: Crescent Books, 1959. 6.Croce, B. The Philosophy of Giambattista Vico, translated by R. G. Collingwood. London: J. Latimer, 1913.
7.Hume, D. A Treatise of Human Nature. Harmondsworth Middlesex: Penguin Books, 1969.
8.Russell, B. A History of Western Philosophy and Its Connection with Political and Social Circumstancesfrom the Earliest Times to the Present Day. New York: Simon & Schuster, 1945.
9.Popper, K. R. The Logic of Scientific Discovery. London: Hutchinson, 1959. 10.Popper, K. R. Conjectures and Refutations: The Growth of Scientific Knowledge. London: Routledge & Kegan Paul, 1963. 11.Popper, K. R. Objective Knowledge: An Evolutionary Approach. Oxford: Clarendon Press, 1979.
12.Ayer, A. J. Philosophy in the Twentieth Century. New York: Random House, 1982.
13.Kuhn, T. S. The Structure of the Scientific Revolution, 2nd ed. Chicago: The University of Chicago Press, 1970.
14.Kuhn, W., and Ryffel, K. Herstellung konzentrierter Loesungen aus verduennten durch blosse Membranwirking. Ein Modellversuch zur Funktion der Niere. Hoppe-Seiler's Zeitschrift f. physiol. Chem. 276:145-178, 1942.
15.Wexler, A. S.; Kalba, R. E.; and March, D. J. Three dimensional anatomy and renal concentrating mechanism. I. Modeling results. Am. J. Physiol. 260: F368-388, 1991.
442 I G. G. Pinter and Vera Pinter ¦ Integrative Physiology
For additional information about this article https://muse.jhu.edu/article/405805
Access provided at 5 Nov 2019 03:47 GMT from Miami University Libraries
A SEARCH FOR THE CERTITUDE OF SCIENTIFIC FACTS WITH GIAMBATTISTA VICO AND KARL POPPER: THE IMPORTANCE OF INTEGRATIVE PHYSIOLOGY G. G. PINTER* and VERA PINTERf
It is recorded of the Greek philosopher Cratylus that, having resolved
never to make a statement of whose truth he could not be certain, he was
in the end reduced simply to wagging his finger. —A. J. Ayer. [1]
Some years ago, a friend of ours [2] was lecturing on renal physiology to medical students at the University of Uppsala, when an impatient student, banging down his pencil on the bench, shouted: "Professor, don't give me all those theories, just give me the facts!" Our first physiology professor, G. Mansfeld [3], wrote in the preface of his book summing up 20 years of research: "A single fact is worth more than all the theories and hypotheses of the world."
Having spent several decades in teaching and research, we, too, have
searched for the certitude of facts in science. Our endeavor did not lead
to the success we have expected or, frankly, strongly hoped for. In teaching renal physiology, our experience was that we could not answer all questions raised by students with equal confidence. This was not so solely because in many regards we were ignorant. More often, the reason for our uncertainty was the nature of the question. When questions related to the "conceptual framework" of the subject—e.g., definitions such as clearance or free water, or models of the countercurrent mechanism of the urine concentration—our answers were certain and accu-
rate. But when the questions were aimed at the actual processes of how the kidney works, our answers were less definite and often more equivo*Department of Physiology, University of Maryland School of Medicine, SM, UMAB, 660 West Redwood Street, Baltimore, Maryland 21201, and King's College, London, England.
tWhipps Cross Hospital, Leytonestone, London, England. © 1992 by the University of Chicago. All rights reserved. 0031-5982/92-3503-0786$01.00
436
G. G. Pinter and Vera Pinter ¦ Integrative Physiology
cal: in some cases pertinent experimental results were not in full agree-
ment, in others the interpretation of the results differed, and in yet
other instances there were some other limitations to the certitude of the facts.
Are there facts known to us with certainty about nature? The question may be as old as Homo sapiens, and the oxymoron implied is, indeed, disconcerting. We do not pretend or hope to examine it from the begin-
ning, and our intrusion into epistemology is admittedly amateurish. Nevertheless, after inserting a few definitions of some relevant words, we will make an attempt to find an answer. We propose to seek guidance by the relevant thoughts of two philosophers whose ideas have made lasting impressions on us: Giambattista Vico and Karl Popper.
The American Heritage Dictionary defines both fact and truth in context of knowledge. "Fact: 1. something known with certainty, 2. something asserted as certain"; "Truth: 1. conformity to knowledge, fact, actuality, or logic." About knowledge, A.J. Ayer [1] wrote "the necessary and sufficient conditions for knowing that something is the case are first
that what one is said to know be true, secondly that one is sure ,of it,
and thirdly that one should have the right to be sure."
InDe antiquissima Italorum sapienta [4], published in 1710, Giambattista Vico wrote: "verum et factum reciprocantur, seu, . . . convertuntur." The meaning of this statement is, perhaps, best captured by Bertrand Russell [5]: "For Vico, the condition of knowing something is to have made it. The basic formulation of the principle is that we can only know what
we can do or make." Vico expressed this thought in several ways and in several contexts. Thus: "We demonstrate geometry because we make it: if we could demonstrate physical facts, we should be creating them" [6]. Again, "We demonstrate mathematics, because we create their truth"
[6]. "Verum ipsum factum," a succinct expression of Vico's assertion, has
been interpreted by Benedetto Croce [6] as follows: "The condition
under which a thing can be known is that the knower should have made
it, . . . the true is identical with the created." Croce [6] wrote also this: "Certitude ... is not science."
Vico thus explained our experience when we tried to answer the questions of our students, namely our experience of having been quite certain of man-made theories and concepts while lacking the same certitude about processes occurring in nature. But are Vico's ideas still valid? Has he been superseded by more modern epistemology? We turn to Karl Popper for further guidance.
Among Popper's contributions, two seem to be highly relevant to our question regarding certitude or facts in science. The first is his solution to the problem of inductive reasoning. The second is his recognition of a domain of human creations that he called "world 3." Let us attend
first to the problem of inductive reasoning.
Perspectives in Biology and Medicine, 35, 3 ¦ Spring 1992 | 437
David Hume [7] held that inductive reasoning is invalid' "even after the observation of the frequent conjunction of objects, we have no rea-
son to draw any inference concerning any object beyond those of which we have experience." Of this, Bertrand Russell [8] wrote: Hume's skepticism rests entirely upon his rejection of the principle of induction. ... If this principle, or any other from which it can be deduced, is true,
then the causal inferences which Hume rejects are valid, not indeed as giving
certainty, but as giving sufficient probability for practical purposes. If this principle is not true, every attempt to arrive at general scientific laws from particular observations is fallacious, and Hume's skepticism is inescapable for the empiricist. . . . What these arguments prove—and I do not think the proof can be controverted—is that induction is an independent logical principle, incapable of being inferred either from experience or from other logical principles, and that without this principle science is impossible.
Popper has been given credit for eliminating inductive reasoning
from scientific logic and for redefining the role of theory and hypothesis in the process. According to Popper [9], scientific investigation is, like many other human activities, in essence a form of problem solving: once a problem is identified, solution is sought by trial and error. In scientific research a hypothesis is formulated from which—by deductive reasoning—conclusions are drawn, and these conclusions are then
tested either by experiment or by matching them against known conclusions from other theories with the view of showing that the hypothesis is wrong, i.e., of falsifying it. Even if a hypothesis escapes early falsification by some number of tests of this type, it is not considered to be
verified, since it has to survive many similar tests still to come. When a hypothesis is found to be false, the next step is to modify it or to state a new hypothesis and go through a new cycle of testing the new hypothesis. The repetition of these cycles is infinite, and in the process the "verisimilitude" of the hypothesis with nature can increase. No inductive
reasoning is involved in this scheme; and testing of hypotheses is done with the intent of falsifying them and not of "confirming" or "verifying" them. Popper wrote [10]: "Every genuine test of a theory is an attempt to falsify it. ... A theory which is not refutable is not scientific. . . .
Some genuinely testable theories when found to be false are still upheld by their admirers for example by introducing ad hoc some auxiliary assumption or by re-interpreting the theory ad hoc in such a way that it escapes refutation. Such a procedure is always possible, but it rescues the theory from refutation only at a price of destroying, or at least lowering, its scienfitic status."
The process defined by Popper will not result in facts or positive certitude informing how things are in nature. While the verisimilitude with nature of set hypotheses may keep increasing, our knowledge will still remain encapsulated within changing and evolving hypotheses and 438 I G. G. Pinter and Vera Pinter ¦ Integrative Physiology
will continue to reside on this side of the boundary visualized by Vico, as theories and hypotheses are man-made. This, however, does not mean that our knowledge belongs to the world of subjective ideas. In addition to a world of objects (Popper's world 1), and a world of subjective ideas (his world 2), Popper [11] recognized a third domain to which belong mathematics, works of art, theories, etc., which, although created by human beings, have acquired independent existence from us (his world 3). The continuing quest for increasing the verisimilitude contained in the ever-changing hypotheses about nature belong to Popper's world 3.
Thus, we arrive at the conclusion that facts and positive certainty about nature elude us; instead we find a dynamic universe of science
that contains unfolding conjectures, hypotheses, and theories, and the wherewithal of observations, experimentation, and modelling, etc., that are the tools of this evolution. In this universe error is an organic part of the scientific process, as the intent to reduce it is the driving force of progress towards greater verisimilitude with nature. The demarcation
between science and non-science is whether a hypothesis is testable.
To us this view of science seems more self-consistent and more attrac-
tive than any other view we are familiar with. There are, of course, other opinions, and both Vico and Popper have opponents and detractors of their views. Vico has been said to repeat only the tenets of scholastic philosophers who held that since God created everything God knows everything. Croce [6] showed that Vico's contributions are much more significant and far-reaching than being just a derivative of scholastic philosophy. Popper's claim to have made inductive reasoning unnecessary in scientific logic has not been accepted by everybody, and Ayer [12] drew attention to the point that when a hypothesis is tested according to Popper's scheme, deductions from it are compared to deductions from
other hypotheses that also have an only limited time of survival. Without going into details, it seems that at this juncture Kuhn's [13] insight into potential changes of entire paradigms might complement Popper's
views.
With the simple-minded confidence of amateurs in the power and the limitations of science as we understand it, we should like to examine a
question of whether it is possible to accelerate the process of improving our hypotheses. Are there any shortcuts?
The past two decades in biological and medical research have seen a
new trend toward cellular, subcellular, and molecular dimensions, while
interest in research on organ systems has declined. It might seem conceivable that research on small consistent parts of the living systems should require simpler hypotheses that should be easier to test than on
integrated systems demanding complex hypotheses and more elaborate tests. Is there a ray of hope that here we might have a recipe for an Perspectives in Biology and Medicine, 35, 3 · Spring 1992
439
accelerated growth of the biological and medical sciences? The importance of this question is pointed up by the circumstance that there is a growing number of research workers who seem to believe that certainty
may be achievable in molecular biology. Research on isolated small building blocks of living organisms may result in a rapid accumulation of theories and hypotheses on these objects. However, we should consider that these small building blocks make up larger entities in an integrated fashion, and that these parts are coordinated by feedback loops in a synergistic and balanced organization. This integration of small parts makes it possible that large living
systems are capable of performing functions that cannot be derived by simply adding up the functions of the isolated small parts. An example from the field of renal physiology (to which we like to anchor ourselves) of these emerging qualities is the current status of the
hypotheses related to the mechanism of how the mammalian kidney produces urine that can be more concentrated or more dilute than the
blood plasma from which urine is ultimately made. This ability of the
kidney appeared relative late on the phylogenetic time scale in mammals and to some degree in birds. Current hypotheses attribute only an ancillary role in the urine concentrating and diluting process to specific sub-
cellular or molecular entities (such as the accumulation of osmolytes in cells and insertion of water permeable aggregates into the membrane of some tubular cells). The primary mechanism held responsible for the concentrating ability is that a section of the uriniferous tubules and accompanying blood vessels in the medulla of the kidney become folded in a particular U-shape. The cells constituting these tubules and blood vessels are not assumed to have unique qualities: their permeability and transport characteristics are assumed to be similar to those found else-
where in the kidney. The ability of carrying out the specific concentrating and diluting functions is attributed to the interacting arrangement between various parts of the U-shaped tubules, as well as to the same type of arrangement of blood vessels, and also to the interaction between these tubules and blood vessels—all these in a highly specific topography
[14, 15]. Clearly, in this case long-existing structures and functional
characteristics have been rearranged and integrated whereby a new
function could emerge. It is important to note here that the hypothesis injecting the new idea for the urine concentrating and diluting process was put forward after the potential significance of the entire structure of the U-tubes in the renal medulla was recognized and shown to be
capable of doing concentrating work in a model [14].
This example should remind us that complex systems abound in biology—systems that demand hypotheses that take into account the specific interactions between the constituent parts. We do not try to
deny the necessity and usefulness of studying subcellular and molecular 440 I G. G. Pinter and Vera Pinter ¦ Integrative Physiology
constituents of the living system. We assert, however, that if we intend to approach the problem of how organisms live, such study should derive its problems and targets from the integrated whole in order that essential internal coordinations not be forgotten. To proceed in the opposite direction, i.e., to try building up the integrated system from small constituents without a master plan, is an unnecessarily blind and difficult task, and claims to the contrary are, at best, mirages. Our unsophisticated excursion into epistemology as related to the
current focus of the biological and medical research provides some perspective to raise questions about current practices. The shift in focus and of support of research in these sciences from integrated physiology to molecular and subcellular aspects has been both substantial and longlasting. The effects of long duration of this shift can not be overlooked, since it involves not only the direction of research but also the education of young scientists. Even if we were to concede (an overly generous concession) that current research on subcellular constituents derived all
of its objectives from sources of integrated physiology, these sources are being replenished at the present time at an ever-diminishing rate. Eventually the trend of trying to build up and understand the living organism from small constituents without a blueprint of integrated physiology shall overwhelm us—if it has not started to do so already. If
no corrective action is taken, it is predictable that this trend shall grow quickly out of all bounds since, in this unhappy future, integrative physiology will be taught by teachers whose expertise will be in other fields, and who will keep only one step ahead of their students in reading a textbook that will not have been truly updated for many years or decades.
For all practical purposes, science seems to have unlimited power and potential. In its endeavor to understand the world, however, it also has
some limitations. Vico had the insight to define a limit to our knowledge,
and Popper has developed clear and specific guiding principles compatible with Vico's insight, concluding that falsehood can be rejected with certainty but that the truth about nature remains uncertain in the domain of the theories and hypotheses that have not as yet been falsified. It may be timely to remember the limitations of science when one branch of biological research appears to make implicit claims not only to offer numerous practical successes (which it can deliver), but also to possess
a unique access to certitude about nature (which should remain beyond its reach). REFERENCES
1.Ayer, A.J. The Problem of Knowledge. London: Penguin Books, 1990.
2.Ulfendahl, H. R. Personal communication.
Perspectives in Biology and Medicine, 35, 3 ¦ Spring 1992
441
3.Mansfeld, G. Die Hormone der Schilddruese and ihre Wirkungen. Basel: Benno Schwabe & Co., 1943.
4.Vico, G. B. De antiquissima Italorum sapientia ex linguae Latinae originibus eruenda. Neapoli: Mosca, 1710. 5.Russell, B. The Wisdom of the West. London: Crescent Books, 1959. 6.Croce, B. The Philosophy of Giambattista Vico, translated by R. G. Collingwood. London: J. Latimer, 1913.
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442 I G. G. Pinter and Vera Pinter ¦ Integrative Physiology
