Prologue
Introduction
1. What is the kind of knowledge we can acquire in biology?
1.1. Biology as a natural science
1.1.1. Inductivism
1.1.1.1. Empirical statements
1.1.1.2. Universal explanatory theories
1.1.2. Objectivism
1.1.3. Reductionism
1.2. Biology as a distinct science
1.2.1. The biological object
1.2.2. Evolution
1.2.2.1. Evolution and creation
1.2.2.2. Evolution and reproducibility
1.2.3. The brain
1.2.3.1. The primary objective of brains is to produce behavior
1.2.3.2. Which behavior is to be produced?
1.2.3.3. The foundations of adaptive behavior
1.2.3.4. Consciousness objectifies the world
2. How does biological knowledge help us understand being?
2.1. What is man?
2.2. The mind body problem
2.3. Materialism and religion
2.4. The meaning of being
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This is a preliminary draft, representing my first stages in
pondering about the more general questions that arise when working
as a biologist (citations will be included at a later stage).
This document will probably be eternally under construction - all
helpful comments and relentless critique are highly appreciated!!
on 06-jun-2004
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| Prologue |
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There was a young man who said, "God,
It has always struck me as odd
That the sycamore tree
Simply ceases to be
When there's no one about in the Quad."
"Dear Sir! Your astonishment's odd,
For I'm always about in the Quad,
And that's why this tree
Will continue to be
Since observed by
Yours faithfully
God."
Ronald A.Knox
I think only few people have
tried to develop a metabiology so far. An extensive internet search revealed
only one substantial occurrence: in connection with Richard Dawkins' meme-concept,
ideas (in analogy to genes: memes) are understood as informational organisms
with a biological substrate (i.e. metabiological organisms, see Memetics:
A Systems Metabiology).
This is not, however, in
any way related to what I have in mind. It is, actually, rather the opposite,
as I will try to make clear below.
I will first give an introduction
into my notion of meta-biology and then try to develop my thoughts as thoroughly
as possible.
Of course these are not all my
thoughts. I don't even intend to write anything new. It is just
a condensed version from what I have read and then picked and chosen from
to form my view of a metabiology. Citations will follow sometime.
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| Introduction |
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The
term Meta-physics stems from the ancient greek "tà
metà tà physiká" meaning "that, which lies
behind physics". It was coined as a bibliographical term by the greek
philosopher Andronikos of Rhodos (80 BC) in order to refer to the
philosophical work of Aristotle which followed (i.e. was located behind)
his scientific writings in an 100 BC edition. Metaphysics today refers
to the philosophical discipline that is concerned with the principles
and meaning of being. Whereas physics attempts a systematic description
of the concrete physical world, metaphysics revolves around questions
that progress beyond the concrete. One could put the central metaphysical
question as: what is the kind of knowledge we can acquire in physics
and how does that knowledge help us understand being?
This is not quite correct, since
the "physics" in metaphysics is used as pars pro toto to refer to
the physical world and all science studying it. Can I keep the terms the
way I introduced them anyway?
In analogy to the above definition
of metaphysics, I'd like to propose the central question for a metabiology:
what
is the kind of knowledge we can acquire in biology and how does that knowledge
help us understand being?
I am aware that I subsume
a particular theory of science and a large part of what is commonly understood
as metaphysics under my idea of metabiology. However, as the common denominator
of both topics is biology and both are reflections on levels more abstract
than the empirical science, I still think the term metabiology is applicable.
(any
counter arguments are welcome!)
As the basic metabiological
question is dyadic, my attempt will consist of two parts:
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| What
is the kind of knowledge we can acquire in biology? |
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Knowledge
itself, of course, is not a term whose meaning is self evident. One
could try to understand knowledge as the collection of truth. What
is truth? The most common definition of truth is "the accordance of
a statement with its fact". But when and how is this accordance granted?
If somebody states "There is a unicorn in the
garden, eating roses", can that be true? Usually, these questions
are solved by having several persons agreeing that the accordance
applies. On what basis do people agree on what is true? In our example,
one would take a look out of the window to see whether there really
was a mythical beast in the garden, eating roses. So seeing is believing?
Since there have been no confirmed sightings of unicorns, we don't
expect to see one, if we look into the garden. If we then saw
a unicorn, we would probably check our eyesight, try to catch the
animal and touch its horn etc. We probably would not do that, if we
saw a horse in the garden. Evidently, our senses are not a good source
of truth. Our reliance on our senses depends on previous experience,
on knowledge that has been confirmed by other people. What makes people
eligible for creating truth? In the tale of the
emperor's new clothes, two clever persons are enough to make believe
there was accordance between their statement and the fact. What enables
us to distinguish between truth and deception? Is there a distinction
between them, or do we only believe ourselves and persons we trust?
In our daily life truth is a social matter and rather fuzzy and complicated.
It depends on who makes the statement, how many they are and how much
we want to believe the statement and so forth. It could be a lot simpler,
if truth were defined by an arbitrary convention. If a statement meets
the convention, everybody will agree that it is true. Of course, different
conventions could be used in the different domains of our culture
(e.g. religion, philosophy, science, art) and indeed many such conventions
have been agreed upon both implicitly and explicitly (examples for
these conventions are the pope's infallibility dogma or English law,
which decrees that truth is what a jury unanimously agrees with, and
is agreed to by subsequent jurists). One of the most successful conventions
of truth was adopted by the natural sciences: reproducibility. Sticking
to this convention, the natural sciences have successfully acquired
a specific kind of knowledge, scientific knowledge. It is important
to keep in mind that however successful and dominant this type of
knowledge is for the progress and evolution of mankind so far, it
is only a fraction of the reality we experience: that which is reproducible.
As I have recently learned, such a conventionalist definition of truth
is the logical consequence of radical constructivism (for definitions
see here
and here).
I will elaborate more on the basis
of this epistemological aspect of metabiology at a later stage of this
draft: see section 2.
What part of the scientific
knowledge is biological and how can it be distinguished from the rest?
The answer to this question lies in examining the type of knowledge acquisition
in biology. I think careful study of the most successful methods and strategies
that unify biology with all other natural sciences and those that distinguish
it from them is the key to apprehending what the biological kind of knowledge
might be. |
| Biology
as a natural science |
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When
thinking about the methodology of natural sciences, three basic methods
/ strategies come to my mind. Using induction, objectification and
reduction, scientists have been able to render the natural sciences
the driving force in the cultural evolution of mankind.
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| Inductivism |
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If
knowledge is a collection of truths, then induction is a method how
to arrange these truths. Induction is the abstraction of a more general
statement from multiple particular statements. According to this definition,
there are two processes of induction that take place 1) at the abstraction
of empirical statements (facts) from observations and 2) at the abstraction
of theories from facts. |
| Empirical
statements |
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The
smallest unit in the wealth of scientific knowledge is the emprical
statement or fact (these terms denote the kind of truth they convey:
scientific truth). An observation attains this status, if it can be
reproduced (otherwise it was merely an anecdotal observation). Why
should that convention be better than any other? For us erroneous
humans, there are practical reasons to chose reproducibility: The
reproduction of observations (under various circumstances and in front
of various observers) is used as a means to attain truth by minimizing
the contextual (anecdotal) effects that are necessarily connected
with each single subjective observation and observer (see part 1.1.2.
Objectivism). In this way, we can eliminate the individual errors
that each observer necessarily makes at each observation. There
is no way to eliminate the errors all humans necessarily make!
I think this brief statement suffices
for this section. I will have to deal with it more deeply in section 2:
I will have to give a review of epistemological thought (Hume, Kant, Hegel
and evolutionary epistemology) and discuss the viewpoints of solipsism/realism/constructivism.
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| Universal
explanatory theories |
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In
the first inductive step, we try to assure ourselves that our observations
are facts. In the second step, we infer a more general hypothesis
from one or more of these facts. An hypothesis is a construct that
can produce phenomena that are isomorphic with the empirical statements
from which it was induced. We then use these hypotheses to predict
future observations of which we have no prior experience. An hypothesis
attains the status of a universal explanatory theory if it has successfully
predicted several observations (since the status of hypothesis vs.
theory is not very clearly defined, I will use the term "theory" throughout).
However, there is a logical
problem in this approach: what leads us to believe that we will observe
something in the future if we have observed it several times in the past?
Why do we expect the sun to come up tomorrow, just because it has done
so in the past? Is there a logical reason to believe in constants, a justification
for our belief that the present is like the past, like the future? If not,
is there a way to avoid skepticism and acquire "objective knowledge"? These
are the basic problems around which David Hume's "An
enquiry concerning human understanding" revolves. He comes to the conclusion
that there is no logical justification for our beliefs. Following and further
developing the empiricist tradition of Locke, Berkley and Hobbes, Hume
tried to escape skepticism by commonsense probabilism. With growing experience,
one learns that there are conjunctions between objects, order and universalities
(Section V). Rules derived from these
frequent / reproducible observations tend to be more reliable (probable)
than others (Section VI). However plausible
this seems, it is irrational (it is only a belief) and in no way a satisfying
answer to the questions above. I agree with Popper (1972), who found that
these questions are psychological questions, which do not help us in the
quest for knowledge at all. It is not sufficient to count how often a theory
is corroborated, how many facts there are in favor of a theory. There is
no logical reason to infer "all swans are white" merely because we have
seen hundreds of white swans. However, if we are lucky, we can falsify
an universal explanatory theory by contradicting empirical statements.
Thus, the most important
test-statements that are deduced from a theory are those that do
not confirm but falsify this theory. This closes an inductive /
deductive loop in which there is constant feedback between facts and theory.
Scientific progress is thus characterized by elimination of falsified theories
and creation of new, yet to be tested ones. This means that one can never
be sure that the critical - potentially falsifying - experiment has been
carried out. It becomes evident that we never uncover part of an otherwise
hidden abjectivity, but rather construct a reality with which we can reconsile
future observations. More to this in section
2!
This leads us to the second
major convention in the natural sciences (solving "the problem of demarcation",
Popper, 1972): Only those theories (or statements deduced from these theories)
which are falsifiable by facts are scientific theories (statements).
"The great tragedy of science
-- the slaying of a beautiful hypothesis by an ugly fact."
T.H. Huxley
Is this sufficient for a general
methodology? Can I leave Kant aside in
this matter?
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| Objectivism |
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For
successfully abstracting a general explanatory theory from a collection
of facts it has proven most valuable to take an observational (meta-)position
of higher order than the theoretical framework of the system in question.
In this manner, the degree to which subjective states of the abstractor
enter the theory can be more easily minimized.
Isn't there a better way to explain
this?
When facts are gathered,
the scientist has to take a position on a more abstract level than the
object he is studying. This is important not only because he might otherwise
subjectify the abstraction from his results but also because he
might interfere with each single observation. Most experiments are
designed in such a way that their outcome is not influenced by the presence
of the observer. Natural sciences have been most successful in constructing
theories about a universe that always follows certain universal laws, whether
anyone is observing it or not. Violations of the objectivist credo that
there is a world that behaves the same with or without us are scientifically
rather unsatisfying. Albert Einstein was never able to concur with the
conclusions that were drawn from quantum mechanics: he used to argue "the
old man does not play dice with the universe" when confronted with the
statistical interpretation of Schrödinger's wave-equation.
To evaluate to what extent
we can objectify biological research, it is indispensable to examine the
biological object more carefully.
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| Reductionism |
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Our
understanding of the world is structured hierarchically, i.e. we perceive
the world as composed of different levels of complexity. The human
mind tends to look for the simplest possible components in a system
and assign levels to different assemblies of these components. The
smallest particles in the universe, for example, are assigned to the
level of physics. A large enough assembly of these particles is assigned
to the level of chemistry. When is that assembly "large enough"? As
soon as the facts of the whole complex of particles can be explained
more easily by a chemical theory than the facts of the sum of the
particles by a physical theory, without loss of explanatory content.
(Does that make any sense at all?)
The same is true for the transition from chemistry to biology: as
soon as it is easier to explain the facts of a whole complex of chemical
objects with a biological theory than it is to explain the facts of
the sum of the chemical objects with a chemical theory (without losing
any explanatory content), the whole complex of chemical objects is
called a biological object. (Is this
application of Occam's Razor admissible?)
This does not necessarily
mean, however, that biology has to be entirely reducible to physics and
chemistry. If there are instances, where the whole constitutes more
than the sum of its parts, some explanatory content were lost by the reduction.
It does mean, though, that contradictions between biological facts on the
one side and physical or chemical facts on the other side are not admissible.
Reductionism and Occam's
Razor are logical consequences of inducing general explanations from particular
observations. If the goal is to find one (comparatively simple) theory
explaining a complex of observations, a simple theory will always be favored
over a more complex theory, if their explanatory value is equal. Large
efforts have been made to find the ultimate consequence, the "theory of
everything" which generalizes all current theories. However, until now,
no-one has been able to construct such a theory.
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| Biology
as a distinct science (particular methodology) |
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So
far, I have only tried to give a short description of elementary scientific
methodology. Much has been written about this (and
I will refer to my still to be created references for further reading.)
and I hope there will be only
little dispute as to biology belonging into this basic framework.
But where within this frame of reference is biology to be found? Certainly,
in principle it shares all the general approaches with the rest of
the natural sciences. But are there specificities that feature biology?
Does it contain methodological elements of its own? Is knowledge acquisition
in biology different from knowledge acquisition in other natural sciences?
We will have to scrutinize the biological object and the kind of knowledge
we can acquire about it to come closer to an answer.
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| The
biological object |
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In
common language biology is understood as the science about life. What
is life? On can think of several criteria that distinguish living
from non-living matter:
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Movement
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Reproduction
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Metabolism
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Cellular organization
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Growth
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Excitability
It is clear that all biological
objects must share the property "life". However, it is a necessary but
not a sufficient criterion. If one investigates into insect flight, for
example, it is not easy to agree that this person is doing biological research.
As we have learned in the previous section (Reductionism), all objects
in this universe are physical objects. If it is easier to apply a chemical
or a biological theory to explain certain observations of a physical object,
it becomes a chemical or biological object. In other words, insect flight
is a physical object, if e.g. only the aerodynamics are studied. As soon
as muscle contraction or the evolution of wings is under study, it becomes
a biological object. A scientific object is thus determined by the type
of theory that is used to explain the facts of that object. But how
do we know that the method in question (e.g. aerodynamics or muscle contraction)
belongs to a particular science?
It now becomes evident that
by elaborating at the criteria that constitute the biological object we
will arrive at a canon of properties that in turn constitute biology as
a particular natural science.
To be continued... (I might cite
Wolbert 1978 from here on)
Since now we have some criteria
at hand to determine the biological object, this might be the time and
place to shed some light on a very basic property of this object. Observations
from a biological object are hardly ever reproducible in the strict sense.
This can be easily exemplified: at some point, every biological object
comprised either parts or single or a collection of individual living organisms.
Because every single organism always differs from any other organism to
a certain extent (even if it is genetically identical) and because every
organism changes over time, observations on one individual (or parts or
assemblies thereof) can never be exactly reproduced (not even in the same
individual). This is inherent to the biological object and is usually not
critically dependent of the accuracy of the measuring devices. Errors of
measurement can be found in every empirical science. System immanent deviations
between otherwise identical observations are unique to the biological sciences.
With one notable exception: Quantum physics. Just as quantum physicists
have to resort to statistical interpretations of their data, most biologists
use statistics to estimate the reliability of their observations. This
is definitely a weakening of the prime scientific convention of truth.
However, since there is no such thing as absolute truth anyway and moreover
the agreement as to when an observation is called "reproduced" critically
depends on convention as well, this is only a quantitative and not a qualitative
deviation from the initial convention. This basic stochasticity in the biological object will become important below, when the role of biological knowledge for our understanding of being is discussed. It is pivotal, for example, for a biologist's way of assessing the contribution of genetic and environmental factors to any given phenotype.
I think this needs more elaboration?
In the following part I have
picked two prime objects (which most scientists would certainly classify
as biological objects) to exemplify the kind of knowledge acquisition in
biology: Evolution and the brain.
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| Evolution |
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Evolution
is certainly the constitutive biological object that unifies the diverse
disciplines and distinguishes biology from other natural sciences.
(I have more about this subject on my evolution
page.) However, evolution is a historical process. No other natural
science is focussed so tightly towards an historical, thus irreproducible
process. It is commonly agreed upon, that evolution does not follow
any predestined goal or aim. An historical random walk through an
evolutionary landscape as the tying knot for an increasingly diverse
science?
Even worse, according to
the definition above, the empirical statement about evolution as the cause
for the origin of species can not be falsified and is therefore not a scientific
statement. If the constitutive element of biology is neither reproducible
nor falsifiable and thus does not meet two of the major prerequisites to
be ranked as a scientific hypothesis, why do most biologists accept evolution
and how can scientific methods aid in understanding evolution?
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| Evolution
and creation |
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Luckily, the evolution
/ creation debate is not at all symmetric. Creationists
have a great disadvantage: it is much easier to observe evolution
than creation. There are many experiments showing evolutionary processes
at work in molecular design (e.g. with self-catalyzing RNA), resistance
formation (e.g. in bacteria) or directed change in quantitative
traits (e.g. hair number or fruit shape in plants) using artificial
selection pressures. The number of areas, where the power of evolutionary
processes becomes evident enlarges every day and has now also reached
non biological fields (e.g. computer science, robotics, machine
design etc.). However, as we learned in the section on the problem
of induction, sheer number of observations in favor of an hypothesis
is not a very good argument. Moreover, all evolutionists can show
is, that evolution is working today, but whether it was the cause
for the origin of species is a mere inference of the type "the present
is like the past". If creationists agree to that uniformity principle,
the only logical alternative to creation is evolution and every
instance where evolutionary processes can be shown, falsifies creation
in that very instance (and vice versa). Comparing the number of
experiments that showed creation as the driving force (and falsified
evolution) with the number of experiments showing Darwinian evolution
as the underlying principle (and falsifying creation) reveals a
rather strong bias towards evolution. Evidently, with the growing
body of evidence for evolution, creationism is in constant retreat.
Interesting findings
(Nature 396, 336-342; 1998) prompt
a short detour deeper into this particular
discussion. Since it is not debatable any more that mutation and
selection function to bring about long term adaptive changes (indeed
the principle is used as a tool in developing many of the modern
industries), many creationists have surrendered on this point. Instead
of sticking literally to the bible (as creationists are almost exclusively
Christian), modern creationists admit change in the origin of species.
Darwinism, however, is said not to suffice to explain the means
by which this change is brought about. Modern creationists accept
that "microevolution" (adaptive changes) within species follows
a Darwinian basis, but mutation and selection are regarded as incapable
of producing the large differences between genera. In a groundbreaking
paper Rutherford and Lundquist (1998) have now suggested a molecular
mechanism which would enable a single individual to enrich its genome
with a multitude of mutations, the effects of which will only penetrate
in stress situations. More specifically, they found out that a protein
in Drosophila (HSP90) buffers heritable alterations in other
proteins by binding to them and restoring their initial function.
Only when this HSP90 is lacking during development (by mutation,
by a pharmacological block or by being sequestered by other proteins
in case of stress such as excessive heat), these alterations penetrate
and lead to "phenotypic variation affecting nearly any adult structure".
It is obvious that such a mechanism can collect potentially useful
mutations over a very long time and release them just at the point
when they might be needed: in times of harmful environmental conditions.
Another mechanism that promotes the same effect was found in the
bacterium Escherichia coli - when the cell is subjected to
strong radiation or chemical mutagens, the SOS response to DNA damage
preferentially introduces Adenosine bases at abasic template lesions
in the replicating DNA strand. Again, it is obvious that this will
lead to an increase in the mutation rate (and thus phenotypic variation
for selection to act upon) at just the right point in time. In other
words: in principle, mechanisms such as the abovementioned may have
served to bring about massive phenotypic variation in times of environmental
stress. It is easy to conceive that with such a multitude of variants
together with the strong selection pressure exerted by harsh environmental
conditions, it may take very few generations for large and fast
evolutionary canges to occur. Not only provide these findings mechanistical
explanations for processes for which creationists need a creator,
they also suggest a molecular mechanism by which such prominent
concepts as "punctuated equilibrium" (Eldredge and Gould, 1972;
Gould and Eldredge, 1993) could substantiate.
In two related papers (PDF: 1,
2) in the same journal (Nature,
717, 2002), results are reported that undermine the creationist
argument even more. The researchers found that simple changes in
a single regulatory protein are sufficient to change the gross body
plan from a crustacean-like plan with legs on all body segments
to a more insect-like one with legs only on the three thoracic segments.
Thus, it's not even necessary to accumulate a number of mutations
for large scale morphological changes. It appears not unlikely that
with more research, even more 'macro-evolutionary' mechanisms are
discovered.
I hope this short digression
made it very clear that evolutionary research today is highly dependent
on the assumption of uniformity in time and can only provide circumstantial
evidence for past evolutionary paths. If creationists accept the
uniformity principle they also have to accept the evidence. The
abovementioned findings have filled another gap in evolutionary
theory that "the old man" was supposed to fill. It should also be
clear now, how the concept of evolution could gain scientific status
without being susceptible to scientific methods directly.
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| Evolution and reproducibility |
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Can
an inductive science provide insight into an historical process? As
mentioned in the previous section, it is assumed that evolutionary
rules are a) universal and b) constant in time. Evolutionary models
or experiments generally try to elucidate these rules and thereby
make probabilistic predictions about the time course and direction
of evolutionary processes. Evolutionary biologists do not merely try
to explain evolution a posteriori, which would be tautological (e.g.
"surviving of the survivor"), but rather try to find the causes driving
the historical process still today. Strictly speaking: evolutionary
biologists repeatedly observe the effects of universal evolutionary
laws not the historical evolution. Whether these laws were
in effect when the species originated is not a scientific question,
it is a postulate.
One important point has
to be mentioned when we consider the reproducibility of evolutionary observations:
evolution acts on a dynamical landscape, using the stochasticity of its
underlying mutational and selective processes to produce unique solutions
to each new problem. Evolutionary experiments can therefore be expected
to have different outcomes and time courses for every run. It is the compliance
or non-compliance with evolutionary theory that is tested in such experiments,
not the final state of the studied system.
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| The brain |
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One
product of evolution has received a considerable amount of interest
in mankind's scientific quest: the brain. It seems that there are
currently many reproducible observations made about the brain
(to the extent mentioned above) and most of today's theories about
specific or general brain functions do produce test statements to
falsify these theories. One function of the brain, however,
might not as easily be subjected to all scientific methods as most
other functions. There are reasons to believe that the objectification
of consciousness might fail. In order to elucidate these reasons,
it could be useful to have a glance at the basic organization of brains.
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| The primary objectives of brains: behavior |
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The
brain did not evolve to see, smell or hear. An eye can not be selected
for on its own. Only if the information the senses convey to the brain
is translated into fitness values, (i.e. recognizing a mate, escaping
a predator and so forth) can selection favor organisms with senses.
Ambulant organisms are faced with the problem of adaptively responding
to rapidly changing environmental stimuli. Brains are evolution's
solution to that problem. There is a rather drastic discrepancy in
the behavioral organization of sessile and ambulant organisms: Sessile
organisms only have a very limited capability to actively influence
their living conditions. Thus, their ethograms are dominated by reactive
behaviors. In ambulant organisms, the ability to move around must
have co-evolved very tightly together with a behavioral repertoire
that enables the organism to move around in order to find suitable
habitats. Their ethograms therefore contain largely active
behaviors. One outstanding feature of brains is their ability to actively
/ spontaneously generate behavior. |
| Which behavior is to be produced? |
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Of
course it is of outmost importance for the organism to mainly produce
adaptive behaviors. Evidently, the decision which of the many behaviors
to produce at a given instance may well prove vital. There are, in
principle, two possibilities how to accomplish this task: either with
innate behavior programs (e.g. reflexes, stimulus-response chains
etc.) adapted to each circumstance by evolution or with acquired behavioral
traits, adapted by experience. In the 18th century, part of the empiricist
philosophy of Locke (An essay concerning human
understanding) was the assertion that individuals were born with
a tabula rasa and only experience could establish mind, consciousness
and the self. On the continent, Leibniz envisaged the self as a monad
carrying some knowledge of a basic understanding of the world. The
discussion as to whether nature or nurture are the driving force shaping
cognitive abilities was for a long time considered to be interminable.
Until the 1960s this dispute was still very vivid in the behavioral
sciences: in the tradition of the English empiricists, Skinner's school
of behaviorism
postulated general rules for all types of learning, neglecting innate
differences or predispositions. Lorenz was one of the protagonists
of ethology in Europe, which focused on the inherited aspects of behavior.
It was Lorenz who ended these antagonistic views of behavior in showing
that there indeed are innate programs ("fixed action patterns") and
predispositions in behavior where only little learning occurs. Today,
it is largely agreed upon that nature and nurture are intimately cooperating
to bring about adaptive behaviors. Probably only in very few cases
ontogenetic programs are not at all subjected to behavioral plasticity.
Conversely, the facilities of acquiring behavioral traits have to
be genetically coded for.
This paragraph is actually the
introduction to my diploma thesis.
It fits so well in here :-) I have more about my own brain research on
my learning and memory page.
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| The foundations of adaptive behavior |
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The
degree to which behaviors are innate or learned is a) limited by the
capacity of the brain to store learned or innate behaviors and b)
dependent on the complexity of the environment to which the organism
is adapted. It is essential to keep in mind the intricate interplay
of reactive, spontaneous and learned behavior. Even under extremely
well controlled experimental circumstances, a stream of observed behaviors
will hardly ever be exactly reproduced at a later time. This stochasticity
is vital for the animal to act flexibly in an ever changing environment,
but it can be fatal if an important goal (feed, mate, etc.) has to
be pursued. One could see the actual stream of behaviors an organism
produces as a trade-off between internal set-points and initiating
activity: The momentary deviation from a desired state superimposes
a bias upon the actual field of probabilities for producing certain
behaviors. This bias shifts the range of behaviors that are produced,
towards behaviors that serve to minimize the deviation from the desired
state. Whether these behaviors are then recruited from the pool of
innate or from that of learned behaviors is arbitrary. Such deviations
from internal states are commonly called drives, instincts or emotions
and are a prime mechanism for affecting a wide variety of behaviors
to pursue an adaptive goal (survival, reproduction etc.). For most
of the evolutionary timescale, the only way to globally affect the
interplay between learned, innate and spontaneous behavior was to
use drives, instincts, moods etc. However, as the complexity of the
environment (also the social environment) grew together with the complexity
of the behavioral repertoire, a second mechanism evolved: consciousness.
The advent of internal representation ("thinking") and self-awareness
served very well indeed to produce adaptive behavior. One can imagine
the brain as a device in which drives set the stage for the directive
under which behaviors are produced, and consciousness aids in selecting
the most efficient behavior and creates new behaviors. This implies
that drives function on a global scale, sub-consciously. It
is thought that drives / emotions are a much older evolutionary invention
than consciousness and the evolutionary age of the corresponding brain
areas confirms that view. |
| Consciousness objectifies the world |
|
| |
Consciousness
is the means by which we solve problems either internally (i.e. thinking)
or externally (i.e. by communicating). Having the ability to anticipate
problems and their solutions and abstractly trying out several possibilities
before performing the actual behavior is the basis for objectifying
the world. Consequently internalizing not only problems of everyday
life but also more abstract terms, means treating them as entities
in their own right. Objects from the external world (physical objects)
and from inside (moods, drives, instincts) are subjected to close
scrutiny by consciousness. However, when trying to understand what
consciousness is, it has to objectify itself, which might prove a
hard thing to do. I deem it well possible, that after quantum mechanics,
consciousness research might be the second area where objectivism
fails and final conclusions about the nature of the object can not
be drawn.
to be continued...
|
| Conclusion of part I |
|
| |
to
be continued... |
| How does biological knowledge help us understand being? |
|
| |
to
be continued... |
| What is man? |
|
| |
to
be continued... |
| Know thyself! |
|
| |
to
be continued... |
| Molecular Biology, evolution and the brain |
|
| |
to
be continued... |
| Biology and the human society |
|
| |
to
be continued... |
| The mind body problem |
|
| |
to
be continued... |
| Materialism and religion |
|
| |
to
be continued... |
| The meaning of being |
|
| |
to
be continued... |
copyright © Björn
Brembs 2004. |
