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Dictionary of the History of Ideas

Studies of Selected Pivotal Ideas

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Environment Versus Organism. There seems to be
no difficulty at first glance in differentiating between
organism and environment. As commonly used, the
word “environment” refers to the setting in which the
organism develops and functions; more specifically, it
denotes all the known factors of the external world
as well as those not yet recognized that impinge on
the organism and thus affect its biological nature. Ac-
cording to this definition, the cellular wall, just like
the human skin, sharply separates the organism—
microbe or man—from the external world.

The distinction between organism and environment
becomes quite blurred, however, when one considers
biological nature and external world not as separate
static entities, but as interacting components in com-
plex dynamic systems. Before discussing the knowledge
derived from the natural sciences that bears on the
interplay between environment and organism, it may
be useful to introduce the problem from the opposite
points of view identified (since the seventeenth century,
if we limit ourselves historically to the modern era)
with the philosophies of John Locke and Bishop George

For the modern philosophers of Locke's persuasion,
all our knowledge comes from sensations and through
ideas of reflection on our sensations. Sensation begets
memory; memory or internal reflection begets ideas.
Since only material things can affect our senses, it
follows that mind cannot be separated from the exter-
nal world. John Locke follows Aristotle and Thomas
Aquinas in believing that there is nothing in the mind
except what was first in the senses. Bishop Berkeley
argued in contrast, that if our knowledge of anything
is merely our sensations of it, and if our ideas are
derived from these sensations, then a “thing” has no
objective reality; so that nothing exists “without the
mind.” A thing is merely a bundle of perceptions—that
is, of sensations that have been classified and inter-
preted by the mind. Matter, as far as we know it, would
then be nothing but a mental construct. Berkeley's
point of view makes it just as difficult as John Locke's
to differentiate between organism and the external

The Locke-Berkeley controversy could be profitably
followed through the views of David Hume, Immanuel
Kant, and all the other philosophers who have tried
to understand how man's mind relates to the rest of
the universe. But on the whole professional scientists
have not been much concerned with these problems.
They believe in the reality of the external world and
in the possibility of making some kind of sense out
of its manifestations. This attitude of pragmatic real-
ism, however, is not without ambiguity as was recently


brought out by Michael Polanyi, who was a scientist
before becoming a philosopher.

The way we see an object, Polanyi points out, (in
a lecture before the American Academy of Arts and
Sciences in 1968) is determined by events inside our
body of which we are aware only through the position,
shape, size, and motion of the very object to which
we are attending. We are attending from these internal
processes to the things outside; their qualities are what
these internal processes mean to us. We know the
external environment by attending to it from our body,
more specifically from our internal environment. Fur-
thermore, we know our body by attending from its
attributes to the events of the outside world. This is
precisely what it means to live in our body. Our very
participation in the act of knowing then conflicts with
the attitude of scientific detachment and therefore with
objectivity. For this reason, according to Polanyi, bi-
ologists cannot inquire into the functions of organisms
without keeping in mind the purpose these functions
serve in a particular environment; sociologists cannot
ignore the power of ideals in their analysis of social

The organismic view of biology, as opposed to the
purely chemical view, gives hope that the knowledge
derived from the natural sciences can be related to
the preoccupations of the philosophers who are con-
cerned with the environment versus organism problem.

On the one hand, the very process of living trans-
forms the environment profoundly and lastingly, and
this is particularly true of man's activities. All orga-
nisms impose on their environment characteristics that
reflect their own biological and social nature.

On the other hand, man's perceptual apparatus is
shaped by the environment. Although we obviously
perceive the outside world through our sense organs,
what we perceive, and the way we perceive it, are
conditioned not only by the evolutionary experiences
of the human species, but also by each person's exis-
tential experiences. Because of this inescapable condi-
tioning, the conversion of environmental stimuli into
shapes, colors, sounds, smells, and other purely sensual
impressions can never be completely objective. Since
our individual modes of perception have been produced
during evolutionary development and are continuously
being altered during experiential life, they always in-
tervene between us and the external environment.

Fitness. The changes that occur in organism and
environment as a consequence of the interplay between
the two may be beneficial or detrimental to one or
both components of the system. The quality of fitness
expresses the beneficial results of this interplay.

As used by theoretical biologists, the word “fitness”
denotes the set of attributes enabling a particular orga-
nism to function effectively and to reproduce abun
dantly in a particular environment. Such fitness is
progressively achieved through the multifarious adap-
tive responses that the organism continuously makes
to environmental forces in the course of its life span.

The Harvard chemist and physiologist Lawrence J.
Henderson considered the problem of fitness from a
point of view which appears at first glance different
from that of the biologist, but is in reality comple-
mentary to it. Instead of concerning himself with the
attributes of organisms, Henderson placed emphasis on
the characteristics of the earth which are essential for
life. In his book The Fitness of the Environment (1913),
he pointed out that life as we know it implies the
existence of a certain set of physicochemical properties
in both the organism and the environment. He de-
fended the thesis furthermore that the physicochemical
conditions prevailing on the crust of the earth are
ideally suited—and perhaps uniquely so—for the
emergence and maintenance of life. The fitness of the
earth environment for life has developed progressively
in the course of cosmic evolution. In Henderson's own
words, “Darwinian fitness is compounded of a mutual
relationship between the organism and the environ-
ment. Of this, fitness of environment is quite as essential
a component as the fitness which arises in the process
of organic evolution.”

The use of the same word—fitness—to designate the
beneficial consequences of two sets of processes as
different as the organic evolution of living things and
the cosmic evolution of the earth may appear a seman-
tic artifact and indeed misleading. Yet, it has a justifi-
cation that transcends verbal analogy. As already
mentioned, organisms become transformed by re-
sponding to environmental stimuli, and they simulta-
neously transform the environment which harbors
them. Some of the physicochemical conditions that are
now regarded as essential for most forms of life were
in fact created by living things. For example, the
chemical composition and physical structure of the soil
are determined not only by its mineral basis and by
the effects on it of atmospheric elements, but also by
the effects of the animal, plant, and microbial life it
harbors. Even more striking is the fact that the con-
centrations of free oxygen and carbon dioxide that exist
today in the atmosphere of the earth differ profoundly
from those that prevailed before the appearance of life.
Our present atmosphere is the product of biochemical
phenomena that have been going on since the begin-
ning of life on earth. The compositions and structure
of the soil and of the atmosphere determine in turn
the kind of microbial, plant, and animal life that can
become established, prosper, and multiply in a given
area of the earth at a given time. Thus, life and envi-
ronment evolve simultaneously through a series of
feedback processes.


It is impossible at present to understand how the
organism-environment interplay began, since nothing
is known concerning the origin of life—unless one
counts as knowledge the crude, vague, and unsubstan-
tiated hypotheses that have recently been formulated
to explain how precellular, self-duplicating, organic
systems originally emerged from inanimate matter. It
is relatively easy, however, to imagine what kind of
feedback processes took place between even very
primitive cellular organisms and the physicochemical
environment that prevailed during the early biological
history of the earth's crust. Darwinian fitness now
implies a complex system of mutual relationships be-
tween organism and environment progressively
reached through the evolutionary mechanisms guided
by natural selection. But, as pointed out by L. J.
Henderson, “Fitness of the environment is quite as
essential... as the fitness which arises in the process
of organic evolution” (p. v).

As everyone knows, the earth environment is be-
coming further and further removed from the ideal of
fitness that Henderson had in mind. Most societies seem
willing to sacrifice environmental quality at the altar
of economic wealth and political power. Wherever
conditions are suitable for technological development,
the earth is losing not only its ecological balance and
pristine beauty, but also its fitness for biological and
mental health. The deterioration of the earth is so rapid
that environmentalists are now concerned less with
fitness than with the social and biological dangers of
modern life, in other words with the destructive aspects
of the environmental problem. In fact, the word “envi-
ronment” now evokes almost automatically pollution
of air, food, and water; wastage of natural resources;
exposure to excessive and abnormal stimuli; the dese-
cration of natural and humanized landscapes; in brief,
the thousand devils of the ecologic crisis. Yet, there
are other aspects of the relations of the environment
to life that are at least as interesting scientifically, and
as important practically, as are the nefarious effects
of human activities on environmental conditions.

Environmental factors exert such a powerful gov-
erning influence on the development of all human
characteristics that they literally shape the body and
the mind. The adaptive responses that man makes to
the physicochemical, behavioral, cultural, and even
historic stimuli that he experiences during the forma-
tive stages of his development constitute the mecha-
nisms through which he achieves biological and mental
fitness to his surroundings.

Most ancient people had empirically acquired the
poetical faith that health depends upon ways of life
in harmony with the natural world and the social
environment. In The Yellow Emperor's classic of inter
nal medicine—the oldest medical treatise in the
Chinese language—men are admonished to live in
accordance with the laws of the seasons, and with the
doctrine of the yin and the yang (Huang..., 1949).
Half a century ago, the Navajo Indians spoke in a
similar vein of their wish to live “in accord with the
mountain soil, the pollen of the native plants, and all
other sacred things.” And comparable expressions of
man's personal and indeed intimate relationship with
his total environment can be found in the legends and
mythologies of all archaic people.

The theme of man's dependence on his environment
pervaded the religious as well as the rational aspects
of early Greek civilizations. Hygeia, from whose name
our word “hygiene” is derived, was one of the personi-
fications of Athena, the goddess of wisdom. She sym-
bolized the belief that men would retain physical and
mental health if they lived within the golden rule, and
according to the laws of reason. In a more concrete
manner, the physicians of the Hippocratic school
taught that man's well-being is influenced by the qual-
ity of air, water, and food; by the topography of the
land and the direction of the predominating winds; and
by his general living habits. The fundamental principle
of the Hippocratic doctrine was that health can be
achieved only by conducting life in accordance with
natural laws and in such a manner that the body and
mind are in harmonious equilibrium with the total

The Greek philosophers and physicians were also the
first to realize clearly, or at least to communicate to
us explicitly, that man's relationships to his environ-
ment go much beyond the problems of health and
disease. In a prophetic passage of his treatise, “Of Airs,
Waters, and Places,” Hippocrates asserts boldly that
food, water, climate, soil, and topography affect not
only man's biological welfare, but also his physical
stature, temperament, behavioral patterns, military
prowess, and even political institutions.

Until late in the nineteenth century, most European
physicians held to the Hippocratic view that human
characteristics, in health and in disease, are profoundly
influenced by the external environment and therefore
could be manipulated and improved by sending pa-
tients to appropriate climates, altitudes, or geographic
situations. Needless to say, this belief was not limited
to medical circles. It was shared by many philosophers,
historians, and critics who believed that man was as
much a product of his environment as of his genetic
endowment. To illustrate the point of view of those
who took the side of the environmentalists in the nature
versus nurture controversy, it will suffice to quote here
a passage from the essay “Uses of Great Men” by Ralph
Waldo Emerson: “There are vices and follies incident


to whole populations and ages. Men resemble their
contemporaries even more than their progenitors.”

We resemble our progenitors because we inherit
from them our genetic endowment. But we resemble
our contemporaries even more, because, within a given
social environment, most members of a given genera-
tion are exposed to the same forces in early life. The
human genetic pool remains essentially the same from
one generation to the next, but its phenotypic expres-
sions change rapidly because the surroundings and
events that shape physiological characteristics and
behavioral patterns differ from place to place and from
one person to another.

As a moralist, Emerson was concerned with the
intellectual and emotional attributes of human beings,
but his aphorism is just as valid for anatomical and
physiological attributes, as can readily be illustrated
by examples taken from recent history and modern life.

The Total Environment. The phrase “surroundings
and events” has been used in the preceding para-
graph in an attempt to convey the multiplicity and
complexity of the factors covered by the word “en-

The total environment refers of course to the com-
plete physicochemical and social setting in which the
organism develops and functions; it includes elements
that may have no biological effect whatever, and also
elements that are biologically active but have not yet
been defined. In describing the physicochemical envi-
ronment, one usually ignores the whole electromag-
netic spectrum except for the wavelengths of light. Yet
it is sufficient to take a radio or a Geiger counter into
a natural situation to realize that there are in the
environment all sorts of forces that are not detected
by the senses; some of them presumably have impor-
tant biologic effects. It is only during the past few
decades that reliable observations have been made, for
example, on the responses of plants, animals, and men
to the cosmic forces that are responsible for the diurnal,
lunar, and seasonal cycles.

Biologists have so far studied chiefly the environ-
mental factors that are intercepted by the sense organs,
and that constitute therefore the perceptual environ-
ment. But our perceptual environment should not be
regarded as representing the total environment. Each
living thing inhabits a perceptual world of its own.
A dog, sniffing the breezes or the traces of a rabbit
on the earth, lives in a world that a man or a frog
hardly perceives. An insect moving at night toward
a potential mate, a salmon crossing oceans toward its
mating ground, or a bird exploring the soil or a dead
tree for an insect, uses clues that are nonexistent for
another species. Much of animal and human behavior
is thus influenced by stimuli which make the perceptual
environment differ from species to species and indeed
from one individual organism to another.

It is being realized more and more that the responses
of organisms to their total environment embrace much
that seemed paranormal but a few decades ago. Ani-
mals have been shown to receive information through
many unfamiliar ways such as pheromones (substances
excreted from the body and perceived by animals of
the same species), ultra sound waves (in bats), and
infrared waves (in moths and pit-vipers). Men also are
sensitive to radio waves and magnetic fields. Weather
changes have been reported to affect the autonomic
nervous systems and various physiologic processes such
as blood clotting and blood pressure. It is also likely
that man, like other organisms, uses exo-hormones for
communication at the biological level. For this reason,
parapsychologists have suggested that extrasensory
perception “is merely a 'crypto-sensory response.'”
There is no doubt, in any case, that various unfamiliar
channels of communication, once dismissed as non-
existent and indeed impossible, enable us to acquire
information from our environment and from each other
without awakening in us a conscious awareness of the

In addition to the factors that are inherent in na-
ture and can—or eventually could—be identified by
physicochemical methods, the total environment in-
cludes elements that exist only in man's mind. For most
archaic people, on a Micronesian atoll for example,
the environment does not consist only of sea, land, and
sky, but also of a host of “spirits” that lurk everywhere.
These factors of the Micronesian conceptual environ-
ment do not have less influence on the inhabitants of
the atoll for having no concrete existence. The “spirits”
are generally innocuous, but they become malevolent
if not properly treated, and can then elicit behavioral
responses that may be even more dangerous than
wounds inflicted by sharks or moray eels.

Nor is the conceptual environment of less impor-
tance in industrialized societies. Whether learned and
sophisticated, or archaic and ignorant, every human
being lives in a conceptual environment of his own
which conditions all his responses to physicochemical,
biological, and social stimuli. These responses eventu-
ally contribute in turn to the manner in which he
shapes his surroundings and ways of life. In our socie-
ties, the conceptual environment is becoming increas-
ingly powerful as a mediator between man and external

The phrase “conceptual environment” is almost
synonymous with what psychoanalysts call superego
and even more with what anthropologists call culture.
Its only merit, perhaps, is to help make clear that the
total environment involves much more than the effects


of natural forces on man's body: it is a determinant
of human behavior and evolution as well as a product
of human intervention.

There is no doubt in any case that for thousands upon
thousands of years, human activities have played an
immense role in shaping the appearance and the
productivity of the earth's crust. Many areas commonly
assumed to be “natural” in reality acquired some of
the characteristics by which they are known today in
the course of civilization. The valleys of the Euphrates
and the Nile were profoundly transformed by human
labor during the Neolithic period. Since that time, all
over the inhabited parts of the globe, arable lands have
been created by clearing primeval forests or irrigating
desert areas. The character of the vegetation is also
largely man-made. Many plants now regarded as
typical of the Mediterranean landscape—the olive tree,
for example—were introduced from Iran; and the tulip
was first introduced into Holland from Turkey as late
as 1675. The moors of England, so celebrated in litera-
ture, used to be covered with forests: they became
deforested through the grazing and farming practices
of the medieval monks, and then again later when the
construction of tunnels by the mining industry created
large demands for timber.

Agrarian and urban areas long retain the characters
imposed on them by the conditions that prevailed
during their early development. The growth of cities
is inevitably influenced by the networks of waterways,
streets, and roads as well as by the kinds of activities
that existed at their beginnings. This shaping of the
natural world by man, in turn conditions his activities
and thereby his biological and mental nature.

In civilized life as well as in plant and animal life,
organism and environment continuously transform
each other as a result of their mutual relationships.
Although it is impossible to dissociate organism from
environment, the choices made by living things, and
by man in particular, exert a directive influence that
guides the organism-environment system into channels
from which there is hardly ever any retreat, and that
imposes a pattern on the development of both.

Internal and External Environment—Le Milieu
Human history during the past two hundred
years provides striking examples of man's desire and
ability to change the trend of his relationships with
environmental forces.

Throughout the nineteenth century, one of the
manifestations of the Hippocratic doctrine, according
to which man can escape disease by living reasonably,
was the interest that prevailed throughout Europe in
the health and ways of life of the noble savage. The
illusion (and it still persists!) was that civilized man
could recapture biological and mental sanity by re
turning to the ways of primitive life in nature. Naive
as it was, and contradicted by epidemiological facts,
this attitude was of practical importance nevertheless
because it created an intellectual climate favorable for
the Sanitary Revolution of the mid-nineteenth century.

If ever men lived under environmental conditions
completely removed from the ways of nature, and
deleterious to health in all ways, it was the proletariat
of the first phase of the Industrial Revolution. Physi-
cians and enlightened citizens could not help noticing
that biological and mental degeneration always ac-
companied dirt, want, and other aspects of the appall-
ing conditions that prevailed in the factories, shops,
and tenements of industrial cities. This awareness led
to the conclusion that it was a social responsibility to
provide the multitudes with pure air, pure water, pure
food, and pleasant surroundings. In Munich, the chem-
ist Max von Pettenkoffer, who was city administrator,
practiced with astonishing success the policies of sani-
tation that he formulated later in his pamphlet, “The
Value of Health to a City,” consisting of two popular
lectures delivered on March 26 and 29, 1873. For him,
collective cleanliness was the surest way to health and
happiness. The sanitary movement in England gener-
ated the “Health and Town Association,” which took
as a goal “to bring home to the poorest... the simple
blessings which ignorance and negligence have long
combined to limit or spoil: Air, Water, Light.” In 1876,
the English physician Benjamin Ward Richardson pub-
lished his book Hygeia: A City of Health describing a
utopia based on what he regarded as rational control
of the environment by social regulations.

The publication of von Pettenkoffer's “The Value
of Health to a City” and of Richardson's Hygeia marks
the height of the nineteenth-century sanitary revolu-
tion. But, paradoxically enough, it also marks its end
because, as these books were being published, the
environmental philosophy that they advocated was
beginning to be overshadowed by the more precise
environmental knowledge derived from laboratory sci-
ence. As a result of the discoveries made in the 1870's,
especially by bacteriologists and nutritionists, the
cleansing of the environment rapidly lost the limelight
to chemical disinfection, vaccination, drugs, and vita-
mins. Charles V. Chapin, the Health Commissioner of
Providence, Rhode Island, symbolized this change of
attitude by stating that it mattered little from the point
of view of hygiene whether city streets were clean or
not, provided microbes were kept under control and
people were protected against infection by the proper
vaccines. Environmental control of health was being
replaced by laboratory control.

The laboratory scientists, who superseded the nine-
teenth-century sanitarians on the health scene, worked


on the assumption that each particular disease could
be equated with the effect of a specific causative
agent—whether this be a microbial pathogen, a nutri-
tional deficiency, a metabolic defect, or a mental stress.
The evidence in favor of the doctrine of specific etiol-
ogy is so impressive indeed that it appears to leave
no place for the rather vague Hippocratic hypothesis
according to which disease results from the breakdown
of the harmonious equilibrium that exists in the state
of health between organism and environment. Hippo-
cratic doctrine has acquired a new and more profound
significance during recent years from the broad impli-
cations of the concepts identified with the names of
Charles Darwin and Claude Bernard. Interestingly
enough, these new concepts were first being formulated
a century ago, precisely at the time when the doctrine
of specific etiology was beginning to gain momentum.

Darwinian evolution through natural selection im-
plies that an organism cannot be biologically successful
unless it is well adapted to its external environment.
Genetic science has defined furthermore how this
adaptation is achieved through selective processes
which are under the control of environmental forces.
As is now well understood, mutation and selection
provide the mechanisms which make for adaptation
to the environment and which progressively become
incorporated in the genetic apparatus of the species.

While mutation and natural selection account for
the evolutionary evolution of species, these processes
contribute little to the understanding of the precise
mechanisms through which each individual organism
responds adaptively to its environment. This comple-
mentary knowledge has evolved in large part from
Claude Bernard's visionary concepts regarding the
interplay between the external environment and what
he called the internal environment. Claude Bernard
formulated the hypothesis that organisms could not
maintain their individuality and could not survive if
they did not have mechanisms enabling them to resist
the impact of the outside world. Whether man, animal,
plant, or microbe, the organism can function only if
its internal environment remains stable, at least within
narrow limits. The constancy of the internal environ-
ment determines in fact the organism's individuality.
In the case of man, it involves not only biological
attributes but also mental characteristics.

The recognition that the internal environment must
remain essentially stable, even when the external envi-
ronment fluctuates widely, constitutes such an impor-
tant landmark in biological thought that Claude
Bernard's phrase “milieu intérieur” has gained accept-
ance in the English language. The most commonly
quoted expression of his law is: “The constancy of the
milieu intérieur is the essential condition of inde
pendent life.” But its most complete expression occurs
in the Leçons sur les phénomènes de la vie communs
aux animaux et aux végétaux

The fixity of the milieu intérieur supposes a perfection of
the organism such that the external variations are at each
instant compensated for and equilibrated. Therefore, far
from being indifferent to the external world, the higher
animal is on the contrary constrained in a close and master-
ful [savante] relation with it, of such fashion that its equi-
librium results from a continuous and delicate compensation
established as if by the most sensitive of balances.... All
of the vital mechanisms, however varied they may be, have
always but one goal, to maintain the uniformity of the
conditions of life in the internal environment

(Holmes, in
Grande and Visscher, p. 188).

William James was one of the first to recognize the
philosophical importance of the milieu intérieur con-
cept and he referred to it in an editorial in the North
American Review
as early as 1868. But it was probably
Lawrence J. Henderson who did most to make scien-
tists aware of the concept by discussing it in the intro-
ductory chapter of his book Blood, A Study in General
(New Haven, 1928).

Homeostasis, Homeokinesis, and Individuality. In
his book on living phenomena common to animals and
vegetation, mentioned above, Claude Bernard had
guessed that the maintenance of stable conditions in
the body fluids and cells was in some way dependent
upon neural control: “In the animal which has attained
a completely independent life, the nervous system is
called upon to achieve harmony among all these con-
ditions” (Olmsted, in Grande and Visscher, p. 27).

This view was developed much further by the physi-
ologist Walter B. Cannon in his classical work on the
role played by the sympathetic nervous system in
maintaining the internal equilibrium of the body. Can-
non introduced the word “homeostasis” to describe this
phenomenon in his The Wisdom of the Body (1932).

Homeostatic mechanisms are not merely passive.
They involve on the part of the body and the mind
powerful reactions which aim at warding off the envi-
ronmental threat, or at repairing the damage it has
done. In this respect the concept of homeostasis recalls
the Hippocratic view that disease involves not only
suffering (pathos) but also work (ponos). Ponos is the
work expended by the organism in its attempts to
maintain its identity in an ever-changing world.

The responses to biological and mental environ-
mental changes must naturally help the organism to
function adequately under the changed conditions; but,
as already mentioned, the adjustments must remain
within limits precisely defined for each organism. These
two demands apply to populations as well as to indi-
vidual organisms. Whatever its complexity, a biological


system can continue to exist only if it possesses mecha-
nisms that enable it, on the one hand, to maintain its
identity despite the endless pressure of external forces,
and, on the other hand, to respond adaptively to these
forces. The complementary concepts of homeostasis
and adaptation are valid at all levels of biological
organization; they apply to large social groups as well
as to unicellular organisms.

A further elaboration of the milieu intérieur concept,
providing a link with cybernetics, was formulated by
Norbert Wiener when he wrote:

Walter Cannon, going back to Claude Bernard, emphasized
that the health and even the very existence of the body
depends on what are called homeostatic processes... that
is, the apparent equilibrium of life is an active equilibrium,
in which each deviation from the norm brings on a reaction
in the opposite direction, which is of the nature of what
we call negative feedback

(Wiener [1956], p. 291).

Both the theory of evolution (Darwin, Mendel, and
the Neo-Darwinians) and the cybernetic theory of
physiological responses (Bernard, Cannon, Wiener)
provide a dynamic approach to some of the problems
posed by the interplay between man and his environ-
ment. But neither theory deals with the mechanisms
through which each individual person becomes what
he is and behaves as he does in response to the envi-
ronmental forces that have impinged on him in the
course of his development.

The shape of our biological and mental individuality
is influenced by forces which do not affect genetic
constitution, but act on our organism at the critical
periods of development.

W. B. Cannon's and Norbert Wiener's self-correcting
cybernetic feedback represents sophisticated expres-
sions of Claude Bernard's constancy of the milieu
concept. Unfortunately, an uncritical belief
in the efficacy of homeostatic processes tends to create
the impression that all is for the best in the best of
all worlds. The very word “homeostasis” seems indeed
to imply that nature in its wisdom elicits responses that
always bring back the organism to the same ideal
condition. There is no mention of disease in Cannon's
The Wisdom of the Body—as if the homeostatic nega-
tive feedback was always successful in preventing the
nefarious effects of environmental influences, and in
assuring healthy development. This is, of course, far
from the truth.

Furthermore, if it were true that the cybernetic
feedback always returns the organism to its original
state, individual development would be impossible. But
in fact, the situation is very different. Most responses
to environmental stimuli leave a permanent imprint
on the organism, thus changing it irreversibly. It is now
obvious that if an organism were truly in a state of
complete equilibrium, it could not develop. What
characterizes living processes is homeokinesis and not

Individuality develops step by step throughout life,
in part as a result of physiological processes which are
encoded in the genetic constitution, and in part also
because the total environment has formative and re-
pressive effects on developmental processes. Most re-
sponses to environmental stimuli leave an imprint on
the body and the mind, thereby conditioning subse-
quent responses to the same and other stimuli. The
so-called reticulo-endothelial system acts as a memory
organ for those responses which manifest themselves
in the form of immune and allergic phenomena,
whereas the brain is of course the memory organ for
mental processes.

Individuality, therefore, reflects the evolutionary
past as encoded in the genetic apparatus and the
experiential past inscribed in the bodily structures that
store biological and mental memories. Since biological
and mental attributes include at any given time all the
inherited potentialities that have been made functional
by life experiences, and since they are irreversibly
altered by most responses to environmental stimuli,
individuality might be defined as the continuously
evolving phenotype of each individual person. It con-
sists, so to speak, in the incarnation of those aspects
of the environment to which the organism has re-
sponded during its evolutionary and experiential past.

The influence of environmental factors on the
phenotypic expression of the genetic endowment is
particularly striking and lasting during the formative
stages of prenatal and early postnatal life. As com-
monly used, the phrase “early influences” denotes the
conditioning of emotional attitudes and behavioral
patterns by the experiences of early life. But such
conditioning also affects many other biological charac-
teristics, indeed almost every phenotypic expression of
the adult.

The effects of environmental factors on the develop-
ment of individuality are complicated by the fact that
man tends to symbolize everything that happens to him
and then to react to the symbols themselves as much
as to external reality. All perceptions and apprehen-
sions of the mind can thus generate organic processes
of which the environmental cause is often extremely
indirect and remote. In many cases, furthermore, the
person does not create the symbols to which he re-
sponds; he receives them from his group. His views
of the physical and social universe are impressed upon
him very early in life by ritual and myth, taboos and
parental training, traditions and education. These
acquired attitudes constitute the basic premisses ac-


cording to which he organizes his inner and outer
worlds, in other words his conceptual environment.

Whether this conceptual environment is acquired
from the social group, or whether it develops from
individual experiences, the body and the mind are
simultaneously affected by any stimulus—physico-
chemical or mental—that impinges on the organism.

Like the evolutionary development of mankind, the
experiential development of each individual consists
therefore in an integrated series of responses to envi-
ronmental stimuli. Man cannot perceive the external
world objectively without concepts because his per-
ceptual apparatus is shaped by the environment.


Claude Bernard, An Introduction to the Study of Experi-
mental Medicine,
trans. H. C. Greene (New York, 1927; 2nd
ed., 1949); idem, Leçons sur les phénomènes de la vie com-
muns aux animaux et aux végétaux
(Paris, 1878-79). W. B.
Cannon, The Wisdom of the Body (New York, 1932). René
Dubos, Man Adapting (New Haven, 1965); idem, So Human
an Animal
(New York, 1968). L. J. Henderson, The Fitness
of the Environment
(New York, 1913); idem, Blood, A Study
in General Physiology
(New Haven, 1928). Frederic L.
Holmes, “Origins of the Concept of the Milieu Intérieur,”
Claude Bernard and Experimental Medicine, eds. F. Grande
and M. Visscher (Cambridge, Mass., 1967). Hippocrates, Of
Airs, Water, and Places,
trans. W. Jones (New York, 1931).
Huang Ti Nei Ching Su Wen, The Yellow Emperor's Classic
of Internal Medicine,
trans. Veith Ilza (Baltimore, 1949).
E. Harris Olmsted, “Historical Phrases in the Influence
of Bernard's Scientific Generalizations in England and
America,” Claude Bernard and Experimental Medicine, eds.
F. Grande and M. Visscher (Cambridge, Mass., 1967). Max
von Pettenkoffer, “The Value of Health to a City,” Bulletin
of the History of Medicine,
10 (1941), 487-503. Benjamin
Ward Richardson, Hygeia: A City of Health (London, 1876).
Norbert Wiener, “The Concept of Homeostasis in Medicine,”
Transactions and Studies of the College of Physicians in
20 (1953), 87-93; idem, I Am A Mathematician
(New York, 1956).


[See also Biological Models; Conservation; Environment
and Culture;
Evolutionism; Genetic Continuity; Primitiv-
ism; Psychological Theories.]