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Handled intelligently and reasonably, the debate between evolution
(the theory that life evolved by random mutation and natural selection) and intelligent
design (the view that life is the product of intelligent plan by a higher
being or designer) could be an exciting catalyst for students to learn
how science works and what its limitations are. But, sadly, schools typically
do not teach subjects intelligently and reasonably. So the subject is culturally
divisive rather than educationally and intellectually useful. This is particularly
sad because some of the best of what can be said on both sides was written
clearly and beautifully more than 200 years ago and could easily serve
as the foundation for teaching about the nature of science, the nature
of rationality, and the nature of thought.
First, I am not talking about the Biblical account of creation as a
literal guide, because that does not square with the abundant empirical
evidence we have about the origin of life and the universe. Anyone who
would choose to believe literally the Biblical story of creation over the
empirical geologic, chemical, physical, biochemical, and biological evidence
of the nature of evolution is free to do so in a democracy, just as one
is free to ignore evidence about anything in life. But being free to be
ignorant and irrational, even in groups, does not make one knowledgeable
and rational. Many people who claim that the theory of evolution is stupid
do not even know what the theory is. They falsely characterize it as the
view that fish grew lungs and legs, and man comes from monkeys. There is
no reason to debate people who hold this view, because they are not interested
in looking at evidence in a reasonable way. They are only interested in
maintaining their conclusion without letting any facts intrude.
The more interesting and useful debate between intelligent design and
evolution is one that predates Darwin’s
Origin of the Species
by more than 50 years, and recently has taken a more sophisticated biochemical
turn.
Yet even that debate fosters a false dichotomy, seeming to demand a
choice between two options which are not necessarily mutually exclusive
nor even exhaustive of the possibilities. The specific argument from design
I have in mind shows a major hole in the theory of evolution that needs
to be accounted for scientifically (empirically) if possible. That argument
from design, however, jumps to a faulty or hasty conclusion about the significance
of the problem for science. It merely points out a scientific problem about
evolution that is yet to be solved. It is not a catastrophe for or disconfirmation
of the theory.
Then finally, there is a much deeper philosophical problem behind all
this, which is the question of what counts as an explanation, or a satisfying
explanation in the first place, because it may be that even science does
not really give explanations, but only shows patterns that give certain
results, some of which seem to be satisfying psychologically and some of
which do not.
When I was a child, an uncle showed me a magic trick – making a toy
car move by waving his hand over it without touching it. I asked how he
did it, and he showed me a magnet in his hand. I had never heard of a magnet
before, and I did not understand how the magnet made the car move. So I
didn’t understand how the magnet made the car move any more than how
his hand made the car move. He couldn’t answer that, and I am not sure
that anyone can. We know in some sense how magnetism works but not why
it works.
We just know that nature works in certain ways, but we do not really
get to find out why. We can sometimes find mechanisms or patterns that
psychologically satisfy our curiosity at least temporarily, but one could
always ask why the mechanisms work as they do to give the results they
do, and what causes the patterns to be the way they are. It is just that
sometimes we do not ask any further because we are somehow psychologically
satisfied by what we observe. But what makes for a “satisfying” answer
is itself an interesting question. To take just one example, it does not
make us curious that liquids and gases can mix but solids cannot, even
though solids have plenty of empty space between the parts of their atoms.
Why can’t solids mix in the same way liquids or gases do? Why can’t
we pass through walls in the same way we pass through air? Or to take another
example, science books say we can increase an object’s potential energy
by raising it higher above the ground, thus “adding potential energy
to it” – hence if it falls, it hits harder. But we can also increase
the potential energy of an object by digging a hole under what it sits
on. But it ought to seem odd that we can add energy to an object without
doing anything to it, but instead by doing something to the ground
under it. Therefore the concept of potential energy ought itself to seem
odd.
In 1802, more than 50 years before the publication of Darwin's Origin of the Species, William Paley published Evidence of the Existence and Attributes
of the Deity. In that insightful book, he had a most ingenious argument
against evolution as a complete explanation of the origin of life
-- an argument that is still relevant today, particularly when put in biochemical
terms at the molecular and genetic level. Specifically what Paley argued
was that if we found a watch out in the middle of nowhere, we would postulate
that someone designed and made it – even if it did not keep perfect time,
even if it did not work at all, even if we found that it could reproduce
other watches (and thus might itself have been made by a prior watch –
thus shifting our question to what made the first watch, rather than perhaps
the particular one we had found). He argues that the human eye is far more
sophisticated in many ways than a watch, and therefore it would be absurd
to argue that the watch must have been designed but that the eye could
have just come about by some sort of random chance, even in combination
with some kind of theory of evolution – the idea of which preceded Darwin.
We would never say the watch might have just evolved out there in the woods
or the desert or the bottom of the ocean. Why should we take the watch
as evidence of design, but not the human eye?
Darwin pointed out and demonstrated, what is reasonable and observable,
that mutations occur in species, some of which give rise to new species
or new varieties within a species. When, under given environmental conditions,
those mutations are not fatal to the new variety or species before it can
reproduce, it will survive and perpetuate. When the mutations are helpful
for survival and/or propagation under some given environmental conditions,
the species will even flourish. Biology books give many examples of how
this has been seen to work.
What is not answered, nor necessarily even addressed by the theory
of evolution itself, is how or why extremely complex mutations arise that
can be of benefit. I think it was Bertrand Russell, certainly no champion
of religion, who said something like the odds that a complex organism could
benefit from a random mutation is similar to the odds that efficiency of
a grandfather clock might be improved by shooting a bullet into it. The
question is how in an intricate organism beneficial complex molecules arise
from seemingly random mutations. But simply asking the question of
how complex mutations can arise and be beneficial, and then postulating
a designer, avoids the question rather than answering it. There may be
a natural or scientific explanation.
As an illustration of the problem, at the biochemical level, we could
look at the hemoglobin molecule, among a multitude of other molecules and
processes, which is very intricate in how it works, based in part on its
complex structure. But hemoglobin molecules did not just spring up whole
cloth from one mutation, and they would be of no use if they did arise
unless there was blood and a system of oxygenating it and transporting
the oxygenated hemoglobin molecules to where the oxygen could be unloaded
and utilized. Perhaps we have millions of molecules in our bodies that
have yet to develop into something else that will serve a useful function,
but it seems odd to think that partially developed hemoglobin molecules
came about and just hung around until one or six more mutations made them
useful. When we look at the intricacy of any of a large number of molecules
and processes in the human body, and even in many lower organisms, their
existence is not explained satisfactory just by the notion of spontaneous
mutation. Many of them take many mutations to arise at all, and far more
other mutations and structures to arise in order to let them have a useful
role or function.
But just because something has a use does not mean it was designed for
that purpose (books can be used as door stops, but they were not designed
for that purpose; and we might plant a tree for fruit or for shade without
intending to kill the grass in its shade, even though that might be the
result). But when something extremely complex turns out to have a crucial
function in an even more complex organism, it seems, as Paley pointed out,
too incredible to just have come about by chance. What we want to know
is what the mechanism is that brought it all about and assembled it all
in the right system at the right time. We can accept that random mutations
occur. But random mutations seem hardly likely to have produced hemoglobin
molecules in beings with lungs and a blood stream.
Of course mutations that are beneficial for the survival and reproductive
benefit of a species will help it flourish, but that does not explain how
complex mutations come about at just the right place and time in order
to serve a beneficial and crucial function. We need a mechanism in nature – in chemistry or
physics – that accounts for the rise of complex molecules that can have
a beneficial function even if they were not designed for a particular purpose
by a designer. Without such an explanation, evolution and natural selection
just by themselves do not satisfactorily account for the origin of human
life in the complex way it works, particularly at the biochemical level.
What is missing – the problem pointed out by Paley – is just as important
as what we know. We know that mutations come about and serve with natural selection
to explain the rise and demise or flourishing of a species. But while it is
easy to see how harmful mutations can arise – since any “bullet”
to a complex mechanism is likely to be harmful, the origin of multiple, jointly necessary, complex, functionally
useful and beneficial mutations at all is still an enigma that needs explanation.
In short, as Paley's arguments from design persuasively demonstrate, evolution
does not explain or answer the most interesting questions about the origin
of human life. And though the theory from design points that out, its explanation
is not satisfying either, for even if it were true that design plays some
part, we would want to know how the process works to bring that design
into effect. The process is a scientific or empirical and philosophical
question, whether there is intelligent design at work ultimately or not.
The really interesting scientific question about all this, whether there
is design or not, is how complex beneficial mutations arise. What is the
mechanism or mechanisms that produce them? For it seems there must be
more to it than just random chance or random mutation.
These are all fascinating issues that should be alive in schools because
they are part of our intellectual and cultural heritage and because many
students otherwise bored with science and with school as it is taught today
would find them stimulating and challenging. It would lead many students
into an interest in science, psychology, and philosophy who will otherwise
never even know about them. But to do this it has to be taught with sensitivity
and understanding. And those are rare commodities today in the cultural
divide.
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This work is available here free, so that those who cannot afford it can still have access to it, and so that no one has to pay before they read something that might not be what they really are seeking. But if you find it meaningful and helpful and would like to contribute whatever easily affordable amount you feel it is worth, please do do. I will appreciate it. The button to the right will take you to PayPal where you can make any size donation (of 25 cents or more) you wish, using either your PayPal account or a credit card without a PayPal account. |