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A PLAIN GUIDE TO
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Intelligent Design
A struggle is presently being waged
amongst Christians in many lands about how to understand the origin of the
universe. Those who wish to retain a traditional theological system of thought
are promoting the idea that the natural order we humans experience exists
because God designed it that way. Others are
less sure.
The idea that our world was created by a
divine power is as old as humanity itself. It has been refuted by many and
affirmed by many over the ages. Affirming creation became more fashionable in
the late 20th century.
More and more people now suppose that we can be sure that God created our world
and the universe.
It is widely supposed today that the universe had a definite beginning - the so-called "Big
Bang" which took place (according to recent measurements) about 13.7
billion years ago. Eventually, about 5 billion years ago, our
planetary system evolved. Very soon after our planet was formed the first
primitive life evolved. Evolutionary change took place until the life-forms we
know today eventually came about.
The Big Bang theory was first proposed in 1948 by
the Russian-American physicist George
Gamow. He posited that the universe was created in a gigantic explosion and that
the various physical elements observed today were produced within the first few minutes
after the Big Bang. The theory provided a basis for understanding the earliest
stages of the universe and its subsequent evolution.
Available evidence seems to have confirmed
the Big Bang theory:
-
A change in the light reaching us from far-distant stars indicates that
they are moving rapidly away from Earth. Their light
reaches
us at the speed of light reduced by the speed at which the stars are moving
away from us (known as Hubble's Law).
The red parts of the spectrum consist of light moving more slowly than the
blue parts. So we see far distant stars moving away from us as red. This is called the
"red shift".
We
are able to calculate by the degree of red shift just how far away from
earth these
stars now are. And by calculating backwards in time, we can tell roughly when the explosion
which got them moving away from us happened. The current consensus is that the Big Bang
took place about 13.7 billion (13 700 000 000) years ago.
-
The
matter existing in the earliest moments of the universe would have expanded
rapidly after the initial Big Bang. Scientists are able to calculate that
the first elements which would have come into existence as the universe
expanded would have been hydrogen and then helium (the two lightest elements).
As the new universe expanded, the hydrogen and helium would have eventually cooled and condensed into stars and
galaxies by a complex process we are only now beginning to understand.
Residual radiation
from the Big Bang would have continued to cool, until now it should be at a
temperature of about 3 degrees Kelvin (about -270° Centigrade). This background
radiation was detected by radio astronomers in 1965, and has been confirmed many
times since then. It provides
what most astronomers consider to be a cast-iron confirmation of the Big Bang theory.
-
The Second Law of Thermodynamics states that everything has a property called
"entropy". That is, everything in the universe is changing from hot to cold, from
positive energy to
zero-energy, from motion to immobility.
This seems to confirm that the universe had a beginning of some
sort. If it didn't, we'd have no reason to suppose it would ever "end"
by reaching maximum entropy - that is when all matter has ceased moving and
everything is absolutely stable and unchanging. Thus the universe is in a state
of constant change which will lead to its inevitable death. For something to
have an end, it has to have had a beginning.
This is of course a grossly over-simplified account of the Big Bang theory [1].
But it has to be mentioned because some have concluded from it that the universe
is the outcome of intelligent design. Something which makes so much
sense to us must, they say, have been created by an intelligent being.
If the universe was designed by an intelligence, it is argued, then it is a
valid step to suppose that the way the world works is also the result of
intelligent design. That being the case, the designing intelligence (God) must
have intended evolution and its mechanisms. All the species throughout history
have appeared and disappeared according to God's plan. That is, there is nothing
random either about evolution or about the appearance of humanity.
Note that this is not quite the same as a more crude variation also often called
"intelligent design" and now being enthusiastically promoted by some
Christians, mainly in the United States. This variation asserts that God created
the earth as we now know it in
finished form only a few thousand years ago. It is thought by most scientists to
be based on specious reasoning. As Peter Atkins remarks, it
... is not science: it is an untestable assertion pursuing and impelled by
an anti-science, religiously motivated agenda ... [it is] a literary device for
showing that a scientific explanation, in this case evolutionism, provides
superior explanations [3].
One of the leading advocates of the latter version of intelligent design, William Dembski, says
that
... there are natural systems that cannot be adequately explained in terms
of undirected natural forces and that exhibit features which in any other
circumstance we would attribute to intelligence. [2]
In other words, some creatures could not have evolved from simple beginnings because they are
"irreducibly complex". They would die if only one of their features
was taken away. That is, they have a
nature which, if reduced by one factor, would cease to work. An eagle without
eyes could not survive for long. It is impossible, says Dembski, that such life
forms could have evolved from the extremely simple beginnings which evolutionary
theory proposes as the starting points of life today. They must therefore have
been designed by God. The eagle was made with eyes from the start, though from
there it may adapt to changes in its environment.
One illustration of irreducible complexity seems simple enough. Take a mousetrap:
it consists of the base, a catch, a spring and a hammer. All these parts must there if
the mousetrap is to work. Remove just one piece and it will cease to be a
mousetrap. This is sometimes called the "scaffolding objection". Just
as a scaffold supports a building until it is complete enough to stand on its
own, so must certain features first be present if an organism is to develop.
But the
argument is weak. It is possible that a part of any system may initially be to
that system's advantage, though not essential to the operation of the whole. What is
at first only an advantage may later
become essential as that particular living system changes. Thus dinosaurs may have developed something like feathers as a device to make them
look bigger and therefore more dangerous to their natural predators. This would
be an advantage. Some of these dinosaurs may later have adapted to survival
threats by
developing these feathers to assist flight and so escape predation more
effectively. What started as an advantageous later become essential to long-term
survival.
In relation to the argument that the nature of the universe justifies the idea of
intelligent design there are
some important observations:
-
In order to have resulted in our universe as it is, the Big Bang must have occurred within
very tight parameters. It was not a random, chaotic event. If it had been, the elements which
in fact constitute the universe could not have evolved.
The balance of the Big Bang had to be precise down to the last atom in order
for the elements which make up the universe to have come into existence.
This could not, it is argued, have come about by chance. As William Craig puts
it:
... various discoveries have repeatedly disclosed that the existence of
intelligent carbon-based life on earth at this time depends upon a
delicate balance of physical quantities, which is such that were any one
of these quantities to be slightly altered, the balance would be destroyed
and life would not exist. A life-inhibiting universe is inconceivably more
probable than a life-permitting universe like ours [4].
-
In relation to the Second Law of Thermodynamics (entropy), the universe must have started with a high level of
order (negative entropy). What became the universe was originally packed
into an infinitely small, near-perfectly ordered ball of matter (which
Stephen Hawking calls a "singularity" because it can't be observed
or described).
If the universe had been disordered from the beginning, the level of entropy would
have been at its maximum from the start. Nothing could therefore have evolved, since
everything
moves naturally from negative to positive entropy (from order to disorder). For example, the probability of any
disordered state
(positive entropy) organising itself into order (negative entropy) - such as all gas
in a container suddenly rushing into one corner of the container - is extremely tiny (about1 in 10 followed
by at least 18 zeroes). This means that the singularity before the Big
Bang must have been at maximum negative entropy (order) [5].
Despite its highly-ordered initial state before the Big Bang, it turns out that today's
universe could only have resulted from what appear to be improbable
anomalies. That is, a totally uniform universe at the moment of the Big Bang
would simply have remained the same for ever. There would have been no
variations and therefore no change.
As P Davies notes, the universe was in
fact nearly uniform but "... not so exactly co-ordinated as to
preclude the small scale, slight irregularities that eventually formed the
galaxies, and us" [6].
What we know at
present indicates strongly that if these irregularities had been only
slightly greater or smaller, the Big Bang only slightly slower or faster, the elements of the universe
could not have evolved.
-
If the tiny variations of the Big Bang itself indicate
"design", so do the four fundamental forces governing everything physical - gravity,
electromagnetism and what are called the "strong" and
"weak" nuclear interactions. These must all have been intrinsic to
the singularity before the Big Bang.
Gravity Everything which has mass also has the force we call
gravity. The greater the mass, the stronger the gravity.
Electromagnetism Physical bodies also display a
"charge" which attracts or repels other bodies depending on the
nature of their charges. This force is many trillions of times stronger than
gravity. But we usually don't notice it because the positive and negative
charges tend to cancel each other out.
Strong nuclear interaction Forces also operate within the
nucleus of an atom. They can be extremely powerful (about 130 times greater
than electromagnetism) - but because the power falls off so rapidly with
distance, they are not felt outside the nucleus itself.
Weak nuclear interaction Other parts of the atom (leptons) also
display a force. But it is only about one one-hundred- billionth as strong
as electromagnetism (but still much stronger than gravity).
This summary helps illustrate the extraordinary fact
that if the strong nuclear interaction had differed by only as much as one
or two percent, the known chemical elements of our universe could not have
formed. And if the strong nuclear reaction had been different, so would the other fundamental
forces - if they could have been there at all. If the near-perfect regularity in
the initial singularity had been the case, our universe could not have formed as it has.
The technical name given to this variation of "intelligent design" is the Anthropic
Principle, first proposed by Brandon Carter in 1974. William Paley (1743-1805)
proposed an analogy which might help us appreciate the force of the Anthropic
Principle.
Suppose you were walking along a sandy beach and came across a stone. You would be justified in
asserting that it had been there as long as the beach itself had. It would be extremely
difficult to disprove your assertion.
But suppose you stubbed your toe on a fully-functioning watch lying on the beach.
The same argument (that it had always been there) would not be at all convincing.
But why not?
The answer lies in the very high probability that the watch was designed and made, if
only because it is a complex mechanism comprising delicate, intricate parts, but also because nothing is known to reach that kind of
physical arrangement by natural processes. The nature of the watch is such that
it must have been designed and made, whereas rocks are clearly
"natural".
Some think that the same analogy can be applied to the origins of the
universe. They suppose that if the universe shows clear signs of
"design" in the way that the watch on the beach does, it follows that the argument for
a "designer" becomes strong, if not irrefutable.
How persuasive is the anthropic principle in terms of a "designer"
universe?
[A] We normally think about our lives in terms of cause and effect.
I drove too fast (cause) and was given a speeding ticket (effect). I failed to
watch the steps (cause) and took a bad fall (effect). The Treaty of Versailles
after the First World War put too much strain on the German economy (cause)
which led to the Second World War (effect).
It's therefore
natural that we should think of the Big Bang as an effect of some cause (God).
But this may merely be our need to impose some sense (in
human terms) on the universe as a whole, to see in it the same process by which
we make sense of our world.
However, it is just as valid to propose that the
universe is not an effect and has no cause - that it just is. This may not
strike us as intuitively convincing - but it is a
valid conclusion.
[B] Our tendency to assume that the universe is intrinsically ordered
may be the outcome of the way we reason about things in our daily lives.
All reason rests upon the Principle of Contradiction. This states that we cannot validly say that "x" is true and simultaneously that
"x" is untrue (not-x). For example, anyone who claims that he is Napoleon
and
the Duke of Wellington is not only insane but also illogical, since nobody can
ever be a particular person (x) and also another person (not-x).
Without the principle of
contradiction (also known in formal logic as the Law of the Excluded Middle) no
language, including mathematics, can work. And without language we can't reason.
If the Principle underpins all reason, then it is hardly surprising
that the universe is to us an orderly place. It may be that we perceive
the universe as orderly and therefore open to reason simply because reason is the way we make sense of our
surroundings. We need order and therefore we impose it on our environment so
that we can comprehend it.
In other words, this argument turns out to be a
difficult-to-spot tautology. What we're actually saying is
that life exists on our planet because both are able to
support life. Or, to put it another way, everything is ordered because we
perceive it as ordered. The universe is the outcome of intelligence because we
create order using our intelligence.
[C] How strong is our scientific evidence for the nature of the Big
Bang and the subsequent evolution of the universe? At the moment it appears
powerful. But then so did the evidence for a "clockwork" universe in
the decades after Isaac Newton. It then seemed as though certain physical laws worked
without exception and without variation. To Newtonians it was as though the
universe ran like a clock, God having wound it up at the start.
For more than one hundred years it appeared that
humanity would one day discover all the fundamental laws governing the cosmos.
Many supposed that we would eventually be able to order things as we wished by
manipulating these laws. This has proved a pipe-dream. The world is much less
predictable and far more complex than at first thought.
So who is to say that the paradigms we now use to make sense
of the universe - including the Big Bang paradigm itself - will serve for
ever? Just as we have ditched the idea of a clockwork universe, so one day we
may also have to ditch the Big Bang theory.
An example of possible new ways of perceiving the universe is the
uncomfortable new discovery that the observable physical universe
provides only some 20 percent of the universe's total necessary mass. It is now
increasingly certain that the missing 80 percent consists of
"dark matter" - though nobody knows what that actually is.
If we can
one day know something about dark matter, how will that change the way we construe
the universe? We have no way of knowing at present.
[D] An important objection to the Anthropic Principle concerns
the necessity of our universe. Let's accept that our universe evolved from a
Big Bang and that its form, given the nature of that Big Bang, could be no
other. Why should this be the only universe which has developed from a Big
Bang?
In other words. it's just as possible that many other universes arose from the Big Bang or from other Big Bangs, in parallel with our own. The only reason
we don't know about them is that their fundamental laws (or lack of laws) are by definition
different from ours and therefore can't be known by us. We have developed according to the laws of our universe
and can therefore not perceive any other.
Some people suggest that the number of other universes is
infinite - but that's just a guess. It's just as possible that there are two
universes or sixteen or (as some think) nineteen or twenty-three (depending on
the mathematics used).
To sum up, it's not surprising that no other forms of life
exist as far as we know - because we are unable to perceive any life form
other than those which conform to the laws of the universe we inhabit. Ask
yourself: Does a chimpanzee think you're human? [7]
In summary, the Anthropic Principle does nicely for those who need God. But for those who don't, it
's an interesting but unnecessary theory.
Those who propose that "intelligent design" demonstrates the
existence of God have simplified and distorted the evidence beyond what it will
bear. The Big Bang may prove to be an abiding fact. But the existence or otherwise of a
Prime Mover will always be a matter of supposition.
___________________________________________________
[1] The Fabric of the Cosmos by Brian Green, Penguin, 2004
gives the details
[2] The Design Revolution, 2004
[3] Galileo's Finger, OUP, 2003
[4] Theism and Physical Cosmology in A Companion to Philosophy of
Religion, Blackwell, 2000
[5] Living beings are examples of positive entropy being temporarily
organised into states of negative entropy. But we achieve this only at the cost
of increasing entropy (disorder) in the environment around us to the same degree
as we achieve negative entropy (order). That is, to stay alive we pass on
disorder to the universe, thus increasing very marginally the rate at which the
latter is decaying into disorder. The universe dies in order that we may live.
[6] The Accidental Universe, 1982 in God, Humanity and
the Cosmos,
C Southgate et al, 1999
[7] For a much longer discussion of intelligent design which deals (less than
impartially) with the controversy over it in the United States, see the Wikipedia
article.
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