Cite as: Vaz, N. (1999). O ensino e a saúde: um olhar biológico (Teaching and health: a biological view). Cadernos de Saúde Pública, 15, S169-S176. Retrieved from http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-311X1999000600017&nrm=iso
Google Translated from Portuguese to English
O ensino e a saúde: um olhar biológico
Teaching and health: a biological view
Nelson Vaz 1
1 Departamento de Bioquímica e Imunologia, ICB, Universidade Federal de Minas Gerais. Av. Alfredo Balena 190, Belo Horizonte, MG 30130-100, Brasil.
Abstract Living systems are structure determined systems. Teaching is never feasible, but learning is inevitable, a comment by an observer about some aspect of the constant changes occurring while life goes on. Teachers are all those who open up spaces for conviviality and allow congruent changes to take place. There are no instructive interactions in nature. Health and the biology of living systems are phenomena studied in different domains. What is healthy or unhealthy for humans, is defined by human culture. As biological phenomena, health and disease are relational configurations of the organism and its medium. From this perspective, individual health is a social phenomenon.
Key words Health Education; Epistemology; Education; Health
Resumo Os seres vivos são sistemas determinados por suas estruturas. O ensino é impossível, mas a aprendizagem é inevitável, um comentário de um observador sobre algum aspecto das mudanças constantes que ocorrem durante o viver. Professor é aquele que abre um espaço de convivência. Não existem interações instrutivas na natureza. A saúde e a biologia dos seres vivos são fenômenos estudados em domínios distintos, a primeira sendo definida pela cultura. Como um fenômeno biológico, a saúde ou a doença são configurações relacionais do organismo com seu meio e, como tais, são fenômenos descritos no domínio das interações do organismo. Por esse entendimento, a saúde individual é um fenômeno social.
Palavras-chave Educação em Saúde; Epistemologia; Educação; Saúde
In immunology, biomedical interests predominate, but I like to think of my work as biological, and our laboratory at the Federal University of Minas Gerais is called an immunobiology laboratory. When discussing the teaching of health-related topics, I will not refer to vaccines, as would be expected. I will address more general topics. I want to invite you to reflect together on:
1) the biology of teaching;
2) health and biology.
1) The biology of teaching
It seems strange to talk about the biology of teaching. It is natural that biologists are used to studying the relationship between biology and learning; adaptation and evolution are notable examples. In immunology, learning is a natural matter, since, in immunization, the organism seems to deal with molecular novelties; for example, it learns to deal more effectively with germs and viruses. Immunization can be seen as a cellular / molecular form of learning. Many immunologists designate specific immune responses as ‘adaptive immunity’. It is also easy to draw parallels between learning and other biological phenomena.
Here is an important fork, the meaning of which we should not overlook. What about teaching? Does anyone, or anything, ‘teach’ organisms in their evolutionary modifications? Is there any sense in stating that the antigen ‘teaches’ the body to respond immunologically? Does the polio vaccine ‘teach’ a molecular lesson, does it teach the children’s bodies, which makes them vaccinated, uniformly more resistant to polio?
What we have learned about the organization and structure of living things in the past fifty years forces us to answer these questions with an emphatic no. In biology, as in the rest of nature, instructional interactions do not occur. Living beings cannot be bent in arbitrary directions, dictated by their interactions with the environment. This seems contradictory because the first suggested solutions to biological problems tend to be instructive (Jerne, 1967). Bacteria are exposed to penicillin and resistant varieties appear; the factory wall is painted white and the butterflies on them become lighter; a rabbit is injected with sheep red blood cells and specific antibodies soon appear. Everything happens as if penicillin taught bacteria to be resistant; the white of the wall taught butterflies to change color; and the antigen, erythrocytes, guided the formation of antibodies. Then there are the selective explanations: the culture of bacteria already included mutants resistant to penicillin; the butterfly population already included lighter individuals; the rabbit already produced anti-erythrocyte antibodies in small quantities – exposure to erythrocytes only favored the survival of cells that produced them. In all of these cases, everything happens as if an element external to the system interacted with elements of the system and favored them. This is the metaphor in which Darwin relied on the Theory of Natural Selection (Darwin, 1979), to explain the origin of species, because everything happens as if nature selected the most capable individuals, or those with greater reproductive efficiency (Young, 1985).
Thus, although we can attribute certain changes in the characteristics of living beings to learning, it does not result from some form of teaching, but rather from the structure of living beings. They depend on the unfolding of sequences of structural changes triggered by a pairing of interactions between the living being in its environment and the structural dynamics of the living being. Living beings are systems determined by their structure (Magro et al., 1997; Maturana & Varela, 1980; Maturana, 1988).
We are used to seeing teaching and learning as two sides of the same coin, but what we propose here is radically different. We are proposing that there is no instruction (teaching), but learning is inevitable. Learning is a trivial phenomenon, constitutive of living beings, which occurs incessantly due to its internal dynamics and the incessant interactions it performs in its environment.
In the usual conception, interactions with the environment are seen as stimuli and the changes brought about in living beings seen as responses. In immunology, for example, it is possible to speak of antigenic stimuli and specific immune responses. Antigenic stimuli, however, do not teach the body how to respond. To constitute an antigenic stimulus, the material must find in the organism a pre-formed collection of molecular structures in which it can fit with sufficient energy. The molecules and cells that function as if they were specific receptors are already present in the organism before contact with the antigenic material. We can choose to see such molecules and cells as having the function (or purpose) of reacting with the antigen; however, they are components of the organism that only persist as long as they maintain relationships with other components of the organism. The notions of antigenic stimuli and specific immune responses disappear in a language that describes the organism in terms of its internal connectivity. But, going for immunology is not my intention here. So let us return to the initial question.
In a cellular / molecular approach to biological phenomena, we see teaching as an improper notion, while learning is seen as an incessant phenomenon, due to the structural dynamics of living beings. However, how to transport this to the classroom? After all, if there is no teaching, what is a class? What is a textbook?
Learning as a comment
According to Maturana & Varela (1980), students are systems determined by their structure and instructive interactions are biologically impossible. But, if the teacher is not teaching his students, how can we understand what happens in a class, or in a sequence of classes? How can we deny that teaching occurs if the teacher proves, through questions and other forms of assessment, that learning has occurred? It is true that different students undergo different changes in the course of living with the teacher, but everyone, in their own way, seems to learn something.
That students change during coexistence and that each has their own way of changing is not surprising, nor can it be used as an argument to demonstrate that teaching has occurred. We are proposing that learning, as a form of change attributed by someone to someone else (the apprentice), is an inevitable consequence of existing in coexistence. As living beings that we are, we are constantly changing. Such changes occur, in part, as a result of our own internal dynamics; in part, by interactions with elements of our environment. The people we live with are very important elements in the changes we go through as human beings. In fact, if this coexistence was not established in the early periods of our existence, we would not survive and, if we did, we would not acquire characteristics typical of our species, such as the ability to walk upright on two feet, facial mimicry, or speech.
Much of the development of the behavior of birds and mammals depends on recursive and reciprocal behaviors carried out with the help and / or in the company of other animals of the same species – the mother, father, brothers, members of a community. The sexual courtship in many species of birds and fish is a good example of patterns of reciprocal interactions. Maturana refers to behaviors that occur in consensual domains, such as these, of linguistic behaviors.
Human language is a clear example of linguistic behavior, but Maturana includes any domain of interactions generated mutually by the participants as language. Language, seen as a consensual domain, is a standardization of behaviors that, mutually, orient themselves. A coordination of actions, and not a transmission of information, as we usually interpret it.
In our usual interpretation, we make use of what Reddy called “the tube metaphor” (Reddy, 1979). We imagine that communication is something generated at one point (emitter), conducted by a ‘tube’, and delivered to another point (receiver). In this way, there is something that communicates, that moves through the tube. According to Maturana & Varela (1980), this image is false, since it presupposes an instructive interaction. The communication phenomenon does not depend on what is delivered, but on what is happening in the coordination of conduct. This is very different from the idea of transmitting information.
For an observer of this coordination of conduct, however, everything happens as if the transmission of information occurred. We are used to thinking that words and phrases refer to objects and things that exist independently of us. According to Maturana (1993), as biological beings that we are, we cannot know an external reality. We have a structure that reflects a history of interactions with the environment, both recent (ontogeny) and remote (phylogeny), but the environment is not composed of knowable things. When we speak of a world, we are acting as observers of this world and making distinctions in a consensual domain.
One of the central aphorisms in the perspective described by Maturana & Varela (1980: 13) is:
“Everything is said by one observer to another observer, who can be himself.“
The idea of distinctions generated by the observer was not created by Maturana. In Gelstat psychology, for example, Kohler (1925) argued that all perceptual events are internal to the observer. Maturana proposes the idea of consensual domains, of some kind of social interaction in which the observer is necessarily involved. This author does not claim that our discourse refers only to internal events, such as thoughts and feelings (which would constitute a solipsist position), but that all discourses exist in a consensual domain (a domain of coordination of actions between organisms). For Maturana, reality is neither objective nor individual. Typically human activity, language, is a collective activity.
Who’s the teacher?
If we are not transmitting symbolic information to our apprentices – because this transmission is impossible and there are no instructive interactions – the changes in conduct that they go through in living with us depend on this coexistence, this living together. In this new context, who is the teacher? To answer this question, I literally transcribe an excerpt from a Maturana class in Santiago:
– Any other questions?
– Yes, Teacher: What is a teacher? Or, who is a teacher?
(He writes on the blackboard: “Professor, Mestre“.)
– And therefore it is here: to teach. I believe that this concept appears here. What is teaching? Did I teach you the Biology of Knowing? Yes, if someone opens the door to this room …
(He goes to the door, pretends to hear someone knocking on the door, and then apologizes to someone who says in a low voice to another fictional person: “In this room is Professor Humberto Maturana teaching Biology of Knowing”. get back.)
– Did I teach you the Biology of Knowing? In a sense, with regard to responsibility towards the Faculty, I taught them the Biology of Knowing.
– But what did we do throughout this semester?
– Unleash structural changes.
– Trigger structural changes, trigger disturbances. Stupendous! And how did we do that?
– In coordinating action coordinations.
– In coordinating action coordinations. In other words, living together. Of course, once a week, living together for an hour, an hour and a half, two hours, or, some students, who stayed with me for more hours … That was living together. You can say, “Yes, but I was sitting listening”. That was really listening, as I hope.
– They were being touched, happy, saddened, enraged … I mean, all the things of everyday living happened. They messed with the ideas, rejected some. They left here talking this and that … “I’m doing a job ….”. They were immersed in the question: “How to proceed according to what was happening to them, living together, with me, in a space that was being created with me”. So, what was my task? Create a living space. This is teaching.
(Write to the board: Create a living space.)
– Well, I taught you. And did you teach me?
– Of course yes! We teach each other. “Ah, but it turns out that I had the responsibility for the course, and I was guiding what happened.” In a way, yes, in a way, no. In a way, yes, because there are certain things that I understand about the responsibility and the space in which I move in this coexistence, and it had a certain orientation, a guiding thread, a certain purpose. But you, with your questions, were pushing this thing to and fro, and you were creating something that was becoming our living space.
And the wonderful thing about all this is that you accepted that I applied myself to create a space for living with you. Do you realize the meaning of this? It was exactly the same as what happened when you arrived, as children, in kindergarten, and were sad, sulky; mommy is gone, they are crying, “Aaahh, I want my mom”. The teacher comes, offers her hand, and you refuse it, but she insists, then, you take her hand. And what happens when the child takes the teacher’s hand? Accepts a living space.
The same thing happened with you. At some point, they accepted my hand. And the moment they accepted my hand, we became co-teachers. We started to participate together in this living space. And we become, in congruence … In different ways, because, of course, we have different lives, we have different spaces for questions, we have different experiences. But we transformed together, and now we can have conversations that we couldn’t before.
And who is the teacher? Someone who accepts himself as a guide in creating this living space. The moment I say to you: “Ask”, and I accept that you guide me with your questions, I am accepting you as teachers, in the sense that you are showing me spaces for reflection where I must go.
Thus, the teacher is a person who wants this responsibility to create a space for coexistence, this domain of reciprocal acceptance that is configured at the moment when the teacher appears in relation to his students, and a dynamic is produced in which change together.”
Maturana is a radical thinker. He insists that the problem of reality is the most important one faced by humanity today, both for people who are aware of it and for those who are not, because everything we do as individuals or as societies depends on, based on the notion we have about reality (Magro et al., 1997; Maturana, 1988).
Here is one of his opening paragraphs:
“In fact, I claim that the implicit or explicit answer that each of us gives to the question of Reality determines how he or she lives his life, as well as his acceptance or rejection of other human beings in the network of social and non-social systems that he or she integrates. And finally, since we know from daily life that the observer is a living system because his cognitive competence is altered if his biology is altered, I claim that it is not possible to have an adequate understanding of social and non-social in human life if that question is not properly answered, and that this question can be properly answered only if observation and cognition are explained as biological phenomena generated through the operation of the observer as a human being.” (Maturana, 1988: 25).
2) Health and biology
The way of looking and the conversations that guide that look configure what is seen and what is done. Not only that: the way of looking configures the questions accepted as important (Maturana, 1993). In the usual way of looking at immunology, immunological phenomena are linked to health, that is, to the protection of the body against invasion by foreign materials, mainly germs, viruses and parasites. In the way of looking that we propose for immunobiology, immunological phenomena appear as biological phenomena and not as health-related phenomena. In the usual view, this last sentence does not make sense, because health-related phenomena are seen as biological phenomena, for example, as phenomena linked to the life of microbes and the resistance of humans to infections. But health and living can also be seen in another way. I want to make this better.
What constitutes health, or what is desirable in living, is a cultural phenomenon. In Korea, dog meat is part of traditional dishes. Eating the liver and intestines of a freshly slaughtered sea lion, still warm, with its contents including worms, seems to us an abominable habit. For Eskimos, it is an essential conduct for survival in an environment where vitamins are poorly accessible. In many cultures, the human body is deliberately modified, cut, stretched in ways that appear to be mutilations or deformations. For members of other cultures, the flabby and obese physique common in our sedentary ‘civilized’ lives is seen as deformed. The ‘civilized’ man’s diet generates dental caries and metabolic diseases absent in other cultures.
On the other hand, “What constitutes living?” and “What is the organization of living things?” they are questions suitable for current biological research. I say this in the literal sense, as there are already very clear proposals to answer them. Mechanisms capable of generating and diversifying the enormous number of lineages of living beings that have appeared in the history of the planet have been described. These are the same self-generation mechanisms that keep living beings alive today. In this view, we already know how living beings are constituted and we can be more explicit about it.
In describing living beings, Maturana also describes us, human beings and our origin, as observers operating in language. Accepting what constitutes explanations in general and scientific explanations in particular is essential to accept what constitutes living and what living beings are. Therefore, I cannot start from tacitly accepted premises. When I speak of living, I do not speak of health, although the history of living through the ages has been the history of healthy beings.
In the characteristic view of immunology, immunological phenomena appear as phenomena linked to health, that is, to the protection of the body against invasion by foreign materials. I agree with Maturana when he affirms that, in their living, living beings have neither health nor disease. We can see immunological phenomena as living phenomena, part of the constitutive operability of the organism. In this way of looking at health, health emerges as an indirect concern, albeit an important one.
As a cultural phenomenon, health ceases to be an attribute of the organism and becomes a relational configuration of the organism / environment, a phenomenon described in the domain of the interactions of the organism. According to this understanding, individual health is a social phenomenon. In the definition proposed by the World Health Organization (WHO), health is defined by the absence of illness or psychological discomfort. But interdefining health and disease is of little use. Defining what is missing when health is lost matters less than the description of mechanisms capable of generating and maintaining the health of the population and containing social abuse. Even immunological arguments can be used politically. My fellow immunologist Tomaz Mota Santos, now president of UFMG, said that “with vaccination campaigns, governments want the body to resolve our social contradictions“. For Virchow, “if the disease is a consequence of individual imbalance, then epidemics arise in unbalanced societies“.
A quick look at The Cambridge World History of Human Disease (Kiple, 1993), an extensive collection of 1,200 pages, shows that, during human history, infectious diseases were more associated with social phenomena, such as agricultural disasters, wars, major migrations etc., than to the phenomena on which immunology can influence. The plague that hit Europe in the 13th century, for example, came after two years of almost uninterrupted rain. Infectious diseases were not an important factor in the evolution of humans or any other animal (Mckeow, 1988). This is a difficult statement to accept at a time like ours, when threats of plagues appear to resurface that we believed we had overcome.
A change in perspective
When we propose to look at immunological phenomena as biological phenomena and not as linked to health, we propose a non-trivial change, as this has two consequences (Maturana, 1993):
1) All immunology changes, since the phenomena that constitute it change: it is no longer a struggle of the organism against external agents, but a vision of interactions of the organism with itself and with components of its environment.
2) The systemic view of the organism is enlarged: the internal space becomes a closed molecular / cellular relational dynamic, a dynamic that participates in the definition of the organism, instead of being defined by it.
In other words, the notions of attack and defense disappear. The organism is no longer in opposition to an environment that threatens it, and we begin to see the dynamics that integrate the organism and its environment. According to Maturana (1993), the medium in which the organism operates appears in our distinctions when we distinguish the organism, in the same act of distinction. Failing to see the environment as an aggressor, as something external to the organism, we can see it as the scope that makes the organism possible.
In this understanding, as well as the external environment, the internal environment also recovers its dynamic relational character. The organism ceases to be an aggregate of cells, organs and functions and becomes a network of relationships of cellular and molecular productions that appears as a totality in the realization of this dynamic in the environment in which it is defined as such an organism. At the same time, the organism is the environment where many other networks of relationships of cellular and molecular productions appear, which intertwine with the organism in its realization as such. These other networks – such as the nervous system, the endocrine system, the hemopoietic system, or the immune system – constitute units in other domains of description. We will discuss how these different systems intertwine in the organism and how they remain closed in their organization.
Seeing the environment as the environment that makes the organism possible, food – food ingestion – has a great influence on its immune activity, as the most important and everyday form of contact with proteins and, therefore, of environmental interferences of the body on immunological activity. When feeding, the organism contacts a huge variety of macromolecules synthesized by other organisms. The intestinal mucosa is two hundred times larger than the skin and, in addition, houses up to 90% of the body’s immunoglobulin-secreting cells. Many molecules of food eaten are absorbed intact or incompletely degraded, and lymphocyte activation also involves a protein degradation (processing) stage, similar to partial digestion in the intracellular environment.
For these reasons, we consider food as of great relevance for immunological activity and capable of influencing all immunological phenomena, not only from a nutritional perspective, but also in relation to interferences that contact with proteins in the digestive tract may have on activity immunologically and, indirectly, over the entire organism.
Current immunology is a bottom-up approach
Unlike genetics and physiology, which were born from the study of plants and animals, immunology was born associated with medicine and medical bacteriology. It was the first successful form of biotechnology and, in a way, that is what it still is, although not as successful as before. The original goal of producing new vaccines has largely failed. Except for some antiviral vaccines produced in the 50-60s, when tissue culture methods were developed, virtually no major vaccines have been produced since the founding period, despite major efforts and research expenditures. Exceptions would be vaccines for hepatitis-B and for H. influenza. The search for new vaccines, despite many innovations (Dickler & Collier, 1996), remains a basically empirical process.
The great transformation of modern immunology lies, exactly, in the definition of cellular and molecular components involved in immunological activity, an achievement more pertinent to science than to technology. The current difficulty is to apply this huge body of biological knowledge (biochemical, genetic, etc.) specialized to medicine. This is a general problem, not particular to immunology, but it has special characteristics.
Driven by a flood of data on cellular and molecular components, contemporary biological sciences are also concerned with organizing this knowledge into coherent frameworks about the operation of organs, organ systems and the organism as a whole. In neurobiology, for example, cellular and molecular knowledge about the brain needs to be correlated with knowledge about cognition and the conduct of the organism as a whole. To establish these correlations, two trends are identifiable: top-down (from top to bottom) and bottom-up (from bottom to top):
top-down: find out what the brain / mind does → find out how to implement these functions;
bottom-up: find out which components are → discover what large collections of such components can do.
In neurobiology, the top-down approach has been present, as exemplified by the titles of the works of one of the most famous neurobiologists of the 50-60s, Waren McCulloch (MacCulloch & Pitts, 1965; MacCulloch, 1965). The bottom-up approach, in turn, has been gaining increasing prestige, mainly due to its association with information technology and ‘artificial intelligence’, being currently called computational neuroscience, as shown by some of its important titles (Churchland & Sejnowsky, 1988, 1992).
In immunology, for historical reasons, the bottom-up approach has been dominant. Since the invention of the notion of specific antibodies (Von Behring & Kitasato, 1961), the task of immunologists has been:
1) elucidate the biochemical nature of antigens and antibodies;
2) inventing effective immunization schemes against infectious diseases (inventing effective schemes to induce the production of antibodies).
Initially, infectious diseases were understood as a duel between microbial toxins and neutralizing antibodies (antitoxins) or phagocytosis facilitators (opsonins). Only in the 1960s, the cells (plasma cells) responsible for the production of these antibodies were identified. Cellular immunology of that decade, like today, was fundamentally concerned with elucidating the mechanisms of antibody formation. A top-down approach has never taken place in immunology, in which more general concerns, such as proposals to articulate cellular and molecular components in a single system with global properties, were not common. Virtually all theories started from the properties of molecules, like antibodies, or cells, like lymphocytes.
More recently, immunology has undergone a major transformation as it is associated with branches of biochemistry, such as molecular genetics and cell biology. This had two results: on the one hand, the cellular and molecular components have multiplied at a dizzying rate; on the other hand, some fundamental mechanisms of immunological activity were characterized, such as the processing / presentation of peptides and the idiotype / anti-idiotype connections.
All this knowledge, however, has been unable to overcome the problem that immunology set out to solve in its creation: the production of new vaccines and new methods of treatment. Immunologists, in general, as well as the society that finances their research, remain convinced that vaccination is the central objective in the control of infectious diseases. More than a century of repeated failure to produce effective vaccines by injecting innumerable antigenic preparations has not been enough to suggest a change in attitude. Here and there are examples of effective vaccines, such as polio, which can lead to the complete eradication of the disease from the planet (Nature, 1995), as occurred with smallpox (Henderson, 1976).
This insistence on vaccination stems mainly from the belief that the body somehow recognizes foreign materials and organizes its defenses in response to this recognition. It is surprising to see how much of the established immune knowledge has been dominated by unchallenged and even unexamined beliefs.
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