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Gaps, Explanations, &
Darwin's Principle Of Evolution
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General Outline
Gaps in knowledge
Explanations
Mystical "explanations"
Scientific explanations
Darwin's principle of evolution
Introduction
What does it mean that we are conscious beings, that in our own
minds we can create models of ourselves and of the world around
us? How is it that thinking beings such as ourselves exist? In
our awareness of our own personal mortality, each of us wonder,
"What will happen to me, if anything, when I die?" Where did we
come from?
Why does it rain? How do plants get their food from sunlight?
Where did all of the variety of animals and plants come from?
What is life, and where did it come from? Why is this planet
that we find ourselves on suitable for life? Why are there suns
and planets? In fact, what is reality itself? And where does it
come from?
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Because we are conscious beings, we have questions about ourselves and about the world around us.
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Because we are feeling beings, we create answers to try to help us feel good about ourselves and to help give us a sense of control over what would otherwise be an impersonal, uncontrollable universe. If we were to believe in an impersonal world that behaved in a manner that we simply did not understand, wouldn't this lead us to fundamental despair?
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Because we are thinking beings, we understand that our feelings, while they are a part of our internal reality, do not dictate the form or behavior of the world. Reality is what it is. Our human desires do not dictate the nature of reality. As thinking beings, we realize that it is by acknowledging our own ignorance about the world that we truly begin to understand it.
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Let me preface my comments with a quick description of my own
perspective, or bias. I am a "skeptic" in the sense that I
believe that in terms of explaining the world around us, we
should move from the known to the unknown. Our explanations must
not only make logical sense, they must also be connected to
observations about the real world; in other words, a proposed
explanation must draw connections between parts of the world that
we already know about in such a way that we can draw conclusions
about the kinds of observations we could make in the future. If
these future observations do not fall into the pattern predicted
by the proposed explanation, then we must modify our explanation
to make it consistent with the new observations, or we must come
up with a new explanation.
So my personal bias is naturalism. Whether you agree or disagree
with particular comments that I make, I will be drawing your
attention along the lines of the philosophical conflict that came
to a head about 140 years ago.
Let's take a look at one approach in particular. Where do the
various kinds of living things that we see today come from?
The traditional answer for at least the last few thousand years
is that God did it. Regardless of the religious perspective, in
some way or another, by one god or another, life was created by
god or the gods. The behavior of the world is the interplay of
mystical, supernatural forces at work. Even though we cannot
comprehend these mystical forces, we can gain influence over them
by appealing to the gods if we have their favor, or by appeasing
them with sacrifices if we have their disfavor.
Our human ignorance becomes a sophisticated world of our cultural
imagination. Reality becomes tied into our human desires by the
ways in which we create our gods and through the systems that we
create to appeal to them and appease them. As the political
impulse of human society is connected into religion, the lines of
human authority become inextricably tied to particular religious
perspectives.
To question mystical answers to questions about reality, is to
question society and political authority itself.
In this way, the fundamental conflict between science and
religion has come about. The fundamental conflict between science
and religion is a conflict about authority. The authority that it
concerns is the authority to provide explanations about the world
around us. As scientific practice has grown over the last few
centuries, such that today it is has become a very extensive and
sophisticated aspect of our culture, in the realm of what I shall
call "objective explanation," the authority of science has grown
at the expense of religious authority.
In the early 17th century, based on scriptural arguments the
Catholic Church declared
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"The first proposition, that the sun is the center and
does not revolve about the earth, is foolish, absurd,
false in theology, and heretical, because expressly
contrary to Holy Scripture.... The second proposition,
that the earth is not the center, but revolves about
the sun, is absurd, false in philosophy, and, from a
theological point of view at least, opposed to the
true faith."
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In 1613, Galileo wrote about various pieces of evidence for the
Copernican model of the solar system, based on observations he
had made with the newly invented telescope. Three years later,
the Pope ordered him before a court of the Inquisition in the
year 1616.
Explanations about reality must be in accordance with
theological, or mystical, considerations. From the mystical
perspective, observations about reality, and explanations that
are strictly limited to what is observationally possible, are
considered to be, at best, inadequate or irrelevant, at worst,
outright heresy.
The reason for much of the heated conflict between science and
religion has been, and is to this day, about the authority to
explain the world. Since religion has in our history been so
closely tied into our political institutions, to challenge the
teachings of the clerics with respect to explanations of
objective reality is to challenge political authority. (In a
secular society such as ours, it is considered a challenge to
moral authority.)
But there is a more subjective aspect that we must consider.
Religion, being what it is, must "explain" reality in terms of
human feelings and desires, and care must be taken to consider
how our explanations will affect our behavior, our society, our
morals. This religious view of the nature of explanation is
essentially anthropocentric.
The scientific perspective, built up pragmatically over the last
few centuries, is that we must approach our investigation of
nature without regard to our human feelings. Do we like the
implications of a particular explanation? Do we think the
explanation might be detrimental to our conception of human
morality? From the scientific perspective, these kinds of
questions are completely irrelevant.
The anthropocentric perspective views reality in such a way that
the entire creation is oriented toward humans. In general, the
Christian religion, whether Catholic or Protestant, has fought
for an anthropocentric viewpoint against science every step of
the way: earth is the center of the universe, human civilization
is the center of time (the earth and the universe were created
only 6,000 years ago). In the western world, orthodox
Christianity fought the Copernican shift of the earth away from
the center of the (then known) universe. It fought the Newtonian
shift to relative space. It fought geological time that shifted
humans from dominant time to a speck of time among eons. It
fought biological evolution which shifted humans from a specially
created form to simply the current form in a very long line of
biological descent. It fought Einstein's shift to relative time.
One of the fundamental differences between science and religion
is not primarily between two different ways of looking at the
universe, or even of looking at God. The difference arises
because of their two different ways of considering the status of
human beings in the cosmos. Christianity is, as religion should
be, unapologetically anthropocentric.
While acknowledging that we are, of course, human, science
attempts to minimize anthropocentric bias. Are the understandings
about reality that we achieve through science what they are
because we are human, or are they indeed true for any
hypothetical observer, human and non-human alike? Another way to
put it is, do we think we see the atomic structure of matter
because of characteristics peculiar to the human mind, or would
any observer with the ability and inclination also discover the
atomic structure of matter?
Due to evolved traditions of science, the attempt is made to be
truly objective, and we have the evidence all around us that
these traditions work.
In his book A Brief History of Time, the physicist Stephen
Hawking tells us that the change in relative time predicted by
relativity must be taken into account, for example, when using
navigational systems that incorporate satellite information.
Since satellites operate at a point in earth's gravitational well
where there is less distortion of space-time (because they are
farther out from the gravitational center of the earth than we
are), their time runs faster, relative to our time. If this
discrepancy is not taken into account, navigational errors can
amount to several miles (Hawking 1988, pp. 32-33).
This indicates that the general theory of relativity, or
something much like it, is, at some level, a relatively accurate
explanation of reality. And because the difference in time is
indicated not by a human mind, but by the time-measuring devices
in an inanimate object, this indicates that relative time is a
genuinely objective characteristic of reality.
Objective investigation has provided little evidence to indicate
that human beings hold some special status with regard to the
universe. Instead, the evidence seems to point the other way. Our
sun is just one star among a collection of millions of other
stars revolving around a common center. This is our galaxy, the
Milky Way. Our galaxy is just one galaxy in a group of about a
dozen or so galaxies called the Local Group. Our group of
galaxies is just one group among millions of other groups of
galaxies. The immense size of our universe, the sheer number of
galaxies of stars, is something that I think we have great
difficulty trying to comprehend.
We consider this aspect of our universe with awe and wonder.
In his book River Out of Eden, evolutionist Richard Dawkins
writes (p. 133),
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In a universe of blind physical forces and genetic
replication, some people are going to get hurt,
other people are going to get lucky, and you won't
find any rhyme or reason in it, nor any justice.
The universe we observe has precisely the properties
we should expect if there is, at bottom, no design,
no purpose, no evil and no good, nothing but blind,
pitiless indifference.
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As far as the universe is concerned, human beings are not the
center of anything. We are a single atom of hydrogen in the vast
ocean of the sun.
Religion is certainly highly valuable in its appropriate area.
Ministers and theologians, in their appropriate realm, have very
important things to tell us about the human condition. But from a
mystical or anthropocentric perspective, they cannot provide us
with genuine explanations about objective aspects of reality,
about why the components of reality are what they are or why
these components interact with each other to form the patterns
that they do.
Science deals with what is. Religion deals with what
ought to be, from our human perspective. In their proper
realms there is and should be no conflict between science and religion.
On February 12, 1809 — 189 years ago — Charles Darwin was born.
Darwin writes in his autobiography, remembering back to when he
was a teenager:
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To my deep mortification, my father once said to me, "You care
for nothing but shooting, dogs, and rat-catching, and you will be a
disgrace to yourself and all your family."
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Charles Darwin's father had him attend the University of
Edinburgh to be a physician. After two years, Charles realized
this was not what he wanted to do. His father then proposed that
Charles become a clergyman. Darwin tells us that at that time he
"did not then in the least doubt the strict and literal truth of
every word in the Bible." So he attended Christ's College at
Cambridge. During his three years there, Darwin developed an
increasing interest in natural science through some of his
teachers and other acquaintances. Just a few months after his
graduation from Christ's College, he went on the voyage that
would change his life.
It was during his voyage on the Beagle that Darwin realized the
true nature of scientific observation and explanation in his
detailed geological work at various locations along the journey.
And it was his biological observations that caused him to begin
questioning and doubting his own belief in the "literal truth of
the Bible." It was through his very practical geological work
that Darwin became increasingly convinced of the naturalistic
view that science is an orderly investigation of natural causes
and that theology does not serve any useful purpose in such
investigation.
The geologist Charles Lyell served as Darwin's mentor through his
book Principles of Geology, which Darwin studied extensively.
Lyell had written, "no causes whatever have from the earliest
time to which we can look back, to the present, ever acted, but
those now acting; and that they never acted with different
degrees of energy from that which they now exert."
But Darwin was not alone in this naturalistic development in his
thinking. In his book Charles Darwin and the Problem of Creation,
science historian Neal Gillespie describes the
increasing hostility that was growing among the naturalists who
were following the new scientific epistemology against those
scientists who were were still practicing the the old
theologically-based epistemology.
In terms of trying to find explanations of the natural world,
Darwin had come to realize that religious explanations were not
really explanations at all. As early as 1838, he wrote that
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the explanation of types of structure in classes — as
resulting from the will of the deity, to create animals
on certain plans, — is no explanation — it has not the
character of a physical law and is therefore utterly
useless. It foretells nothing because we know nothing of
the will of the Deity, how it acts and whether constant
or inconstant like that of man. The cause given, we know
not the effect.
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In other words, invoking God as an explanation for some
observation about reality does not explain anything, because
God's will can be anything at all. What does saying "This is the
result of God's will" tell you about the world? Let me state this
same idea as a hypothesis: "If this aspect of nature is the
result of God's will, then this idea implies that these are the
kinds of observations that I will see when I carry out my
scientific investigation." Such a hypothesis does not imply any
particular kind of observations at all, so it serves no useful
scientific purpose.
Darwin came to despise appeals to God's divine will or purpose as
attempts to explain aspects of biology and biological history. In
1869, a Hugh Miller wrote that with regard to the decline in the
size of reptiles since the secondary period, we cannot assign a
cause for this general reduction of the reptile class, save
simply the will of the all-wise Creator. But the reason it took
place was to enable the succeeding mammals to flourish. To
Darwin, this kind of explanation was not a genuine explanation at
all. In addition, such so-called explanations, by pretending to
be explanations, impeded further investigation to try to
determine the real causes.
(A few years before the Origin Of Species, a book was
published advocating what came to be called the "Omphalos
argument." This was based on the idea that, just as Adam was
formed as a grown man when he was created, the universe was also
created with the appearance of great age, even though it was
created only about 6,000 years ago.)
In approaching the problem of biological evolution, or, to use
Darwin's terms, "transmutation" or "descent with modification,"
he based his explanation for the mechanism of evolution entirely
on natural causes. And as natural causes, they could have no
forethought, no plan, no design, no purpose.
In writing Origin of Species, Darwin synthesized a brilliantly
argued explanation of the concept of biological evolution. He
brought together ideas from such areas such as geology,
paleontology, biology, animal breeding, and economics. He called
his principle "natural selection."
With regard to purpose or design in evolution, one challenge
Darwin issued was to ask: "If any organic structure could be
shown to have been produced with the good of some other species
as its sole purpose, a condition that would imply foreknowledge,
that would be the end of natural selection."
(This demonstrates how wrong it is to say that the idea of
natural selection is not scientific because it cannot be
falsified. Indeed, in the *Origin Of Species* Darwin wrote a
whole chapter on problems of the theory and how it could be shown
to be false.)
Darwin had a dual purpose in Origin of Species, first to
describe the evidence for the occurrence of evolution, and second
to propose an explanatory mechanism for this occurrence and to
describe the evidence for this mechanism. Darwin was clearly
aware of this distinction in evolutionary concepts, the
distinction between recognizing and establishing the historical
event of evolution and postulating and attempting to substantiate
a hypothetical mechanism of biological change.
This distinction is clearly seen in the structure of his
argumentation in On the Origin of Species. In the introduction,
Darwin wrote:
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...I can entertain no doubt, after the most deliberate
study and dispassionate judgement of which I am capable,
that the view which most naturalists until recently
entertained, and which I formerly entertained — namely,
that each species has been independently created — is
erroneous. I am fully convinced that species are not
immutable; but that those belonging to what are called
the same genera are lineal descendants of some other and
generally extinct species, in the same manner as the
acknowledged varieties of any one species are the
descendants of the species. Furthermore, I am convinced
that Natural Selection has been the most important, but
not the exclusive, means of modification.
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In Darwin's book Descent of Man, written twelve years after
Origin of Species, Darwin wrote:
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I had two distinct objects in view; firstly, to show
that species had not been separately created [event],
and secondly, that natural selection had been the chief
agent of change [mechanism].... Hence if I have erred
in...having exaggerated [natural selection's] power...I
have at least, as I hope, done good service in aiding
to overthrow the dogma of separate creations.
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Many scientists of Darwin's generation and older, agreed that
Darwin had brought together convincing evidence of the
evolutionary history of life, while at the same time they clung
to theological explanations of that history. (Though, of course,
there are the quite notable exceptions, such as Thomas Huxley,
who did more to publicly advocate evolution and natural selection
than Darwin himself did.) Because they thought more along the
lines of naturalism, it was the younger generation of scientists,
who more generally agreed that natural selection was a primary
component of evolution.
Charles Darwin's great achievement was the result of seeing
through the mask that was being used to hide human ignorance with
pretend explanations. By realizing that genuine explanations
needed to be explored, he set out on a path that only a few had
the courage to travel. And he was one of the very few who had
the courage to travel that path in the most consistent way.
This takes us full circle in my short discussion.
I began by stating that because we are conscious beings, we
question the nature of ourselves and we question the nature of
the world around us.
Because of our psychology, we want to have answers to our
questions that will fulfill our emotional desires, our very human
wants and wishes. Even if we don't genuinely understand the
reasons behind the things that we question, we invent answers in
order to give us a sense of control over the events of our lives,
which includes the behavior of the external world that we find
ourselves in.
One critical issue that we must each individually come to grips
with in one way or another is that reality and truth is not
determined by our feelings.
To admit ignorance seems so difficult for so many people. Why is
it so wrong to simply say, "We don't know?" What if we had no
idea what caused rain, or where it came from? What if we had no
understanding of how plants acquired their food? What if we had
no fossil record and no concept of where living things came from?
What if we had no explanation for how our conscious minds can
arise from the matter and energy of our brain? What if we did not
know what will happen to us when we die?
If we don't have genuine explanations, what is wrong with simply
and honestly admitting, "I don't know the answer"? It is only
when we admit that we don't know that we realize we need to do
something to find a genuine answer.
[People] believe what they want to believe and
close their eyes to what they don't want to believe.
They need to think the world is the way they'd like it
to be because having to face up to the reality that it
isn't would be too uncomfortable. So they carry on
pretending because it makes them feel better.
Truth isn't the important thing. The important
thing is to be certain.
| — James P. Hogan, Code of the Lifemaker (1983) |
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(A footnote comment: Implicit in Darwin's principle of natural
selection of inherited characteristics was the idea that the
characteristics were in some sense discrete. Even though they
"mixed" when they came together in forming an animal's body, the
characteristics themselves remained distinct and thus could pass
through from generation to generation. In Darwin's later years,
it was thought that natural selection might very well be
incorrect because it was not known yet that inherited
characteristics were distinct, and it was thus thought that as
characteristics became blended in a population, natural selection
would not have much to work on. In fact, the Catholic monk Gregor
Mendel had discovered the discrete nature of inherited
characteristics in his research on peas, just a few years after
the Origin Of Species was published, thus providing a very
important confirmation of Darwin's principle of natural
selection. Unfortunately, the significance of Mendel's research
was not recognized until about 35 years later, after Darwin had
died.)
Hopefully I have catalyzed your own thinking along these lines,
on the occasion of the birthday of Charles Darwin, 189 years
after he was born.
I close with a quote from Carl Sagan:
Each of us is a tiny being, permitted to ride on the
outermost skin of one of the smaller planets for a few
dozen trips around the local star. ...The longest-lived
organisms on Earth endure for about a millionth of the
age of our planet. A bacterium lives for one hundred-
trillionth of that time. So of course the individual
organisms see nothing of the overall pattern —
continents, climate, evolution. They barely set foot
on the world stage and are promptly snuffed out —
yesterday a drop of semen, as the Roman Emperor Marcus
Aurelius wrote, tomorrow a handful of ashes. If the
Earth were as old as a person, a typical organism would
be born, live, and die in a sliver of a second. We are
fleeting, transitional creatures, snowflakes fallen on
the hearth fire. That we understand even a little of
our origins is one of the great triumphs of human
insight and courage.
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("Snowflakes Fallen on the Hearth" in Shadows of Forgotten Ancestors, by Carl Sagan; pp. 30-31)
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Todd S. Greene
Marietta, Georgia
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I originally wrote this and presented it as a sermon on the occasion of
Darwin's birthday on Sunday, Feb. 12, 1997. So, of course, it is not
intended to be any kind of thorough, logical analysis. It was a sermon.
Thought I'd add it to my website for anyone who might appreciate it for
what it is. (Incidentally, I presented the sermon at a
Unitarian-Universalist Church in Marietta, Georgia.)
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Natural selection, an immensely powerful idea
with radical philosophical implications, is
surely a major cause of evolution, as
validated in theory and demonstrated by
countless experiments.
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— Stephen Jay Gould, The New York Review of Books (1997)
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Reality is what it is —
not what you wish it would be.
– Todd S. Greene
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