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When Religion Steps on Science's Turf & The Emptiness of Theology.rtf
we use our secular judgment of decency and natural justice to decide which ones to follow, which to give up.
Religion on Science's Turf
But that discussion of moral values was a digression. I now turn to my main topic of evolution and whether
the pope lives up to the ideal of keeping off the scientific grass. His "Message on Evolution to the Pontifical
Academy of Sciences" begins with some casuistical doubletalk designed to reconcile what John Paul II is
about to say with the previous, more equivocal pronouncements of Pius XII, whose acceptance of evolution
was comparatively grudging and reluctant. Then the pope comes to the harder task of reconciling scientific
evidence with "revelation."
Revelation teaches us that [man] was created in the image and likeness of God. ... if the human body takes
its origin from pre-existent living matter, the spiritual soul is immediately created by God ... Consequently,
theories of evolution which, in accordance with the philosophies inspiring them, consider the mind as
emerging from the forces of living matter, or as a mere epiphenomenon of this matter, are incompatible with
the truth about man. ... With man, then, we find ourselves in the presence of an ontological difference, an
ontological leap, one could say.
To do the pope credit, at this point he recognizes the essential contradiction between the two positions he is
attempting to reconcile: "However, does not the posing of such ontological discontinuity run counter to that
physical continuity which seems to be the main thread of research into evolution in the field of physics and
Never fear. As so often in the past, obscurantism comes to the rescue:
Consideration of the method used in the various branches of knowledge makes it possible to reconcile two
points of view which would seen irreconcilable. The sciences of observation describe and measure the
multiple manifestations of life with increasing precision and correlate them with the time line. The moment of
transition to the spiritual cannot be the object of this kind of observation, which nevertheless can discover at
the experimental level a series of very valuable signs indicating what is specific to the human being.
In plain language, there came a moment in the evolution of hominids when God intervened and injected a
human soul into a previously animal lineage. (When? A million years ago? Two million years ago? Between
Homo erectus and Homo sapiens? Between "archaic" Homo sapiens and H. sapiens sapiens?) The sudden
injection is necessary, of course, otherwise there would be no distinction upon which to base Catholic
morality, which is speciesist to the core. You can kill adult animals for meat, but abortion and euthanasia are
murder because human life is involved.
Catholicism's "net" is not limited to moral considerations, if only because Catholic morals have scientific
implications. Catholic morality demands the presence of a great gulf between Homo sapiens and the rest of
the animal kingdom. Such a gulf is fundamentally anti-evolutionary. The sudden injection of an immortal soul
in the timeline is an anti-evolutionary intrusion into the domain of science.
More generally it is completely unrealistic to claim, as Gould and many others do, that religion keeps itself
away from science's turf, restricting itself to morals and values. A universe with a supernatural presence
would be a fundamentally and qualitatively different kind of universe from one without. The difference is,
inescapably, a scientific difference. Religions make existence claims, and this means scientific claims.
The same is true of many of the major doctrines of the Roman Catholic Church. The Virgin Birth, the bodily
Assumption of the Blessed Virgin Mary, the Resurrection of Jesus, the survival of our own souls after death:
these are all claims of a clearly scientific nature. Either Jesus had a corporeal father or he didn't. This is not a
question of "values" or "morals"; it is a question of sober fact. We may not have the evidence to answer it, but
it is a scientific question, nevertheless. You may be sure that, if any evidence supporting the claim were
discovered, the Vatican would not be reticent in promoting it.
Either Mary's body decayed when she died, or it was physically removed from this planet to Heaven. The
official Roman Catholic doctrine of Assumption, promulgated as recently as 1950, implies that Heaven has a
physical location and exists in the domain of physical reality - how else could the physical body of a woman
go there? I am not, here, saying that the doctrine of the Assumption of the Virgin is necessarily false
(although of course I think it is). I am simply rebutting the claim that it is outside the domain of science. On
the contrary, the Assumption of the Virgin is transparently a scientific theory. So is the theory that our souls
survive bodily death, and so are all stories of angelic visitations, Marian manifestations, and miracles of all
There is something dishonestly self-serving in the tactic of claiming that all religious beliefs are outside the
domain of science. On the one hand, miracle stories and the promise of life after death are used to impress
simple people, win converts, and swell congregations. It is precisely their scientific power that gives these
stories their popular appeal. But at the same time it is considered below the belt to subject the same stories
to the ordinary rigors of scientific criticism: these are religious matters and therefore outside the domain of
science. But you cannot have it both ways. At least, religious theorists and apologists should not be allowed
to get away with having it both ways. Unfortunately all too many of us, including nonreligious people, are
unaccountably ready to let them.
I suppose it is gratifying to have the pope as an ally in the struggle against fundamentalist creationism. It is
certainly amusing to see the rug pulled out from under the feet of Catholic creationists such as Michael Behe.
Even so, given a choice between honest-to-goodness fundamentalism on the one hand, and the obscurantist,
disingenuous doublethink of the Roman Catholic Church on the other, I know which I prefer.
-----------------------------------------------------------------------Richard Dawkins, one of the world's leading evolutionary biologists, is Charles Simonyi Professor of Public
Understanding of Science at Oxford University and Senior Editor of Free Inquiry.
The Emptiness of Theology
by Richard Dawkins
Published in Free Inquiry, Spring 1998 v18 n2 p6(1)
A dismally unctuous editorial in the British newspaper the Independent recently asked for a reconciliation
between science and "theology." It remarked that "People want to know as much as possible about their
origins." I certainly hope they do, but what on earth makes one think that theology has anything useful to say
on the subject?
Science is responsible for the following knowledge about our origins. We know approximately when the
universe began and why it is largely hydrogen. We know why stars form and what happens in their interiors to
convert hydrogen to the other elements and hence give birth to chemistry in a world of physics. We know the
fundamental principles of how a world of chemistry can become biology through the arising of self-replicating
molecules. We know how the principle of self-replication gives rise, through Darwinian selection, to all life,
It is science and science alone that has given us this knowledge and given it, moreover., in fascinating, overwhelming, mutually confirming detail. On every one of these questions theology has held a view that has
been conclusively proved wrong. Science has eradicated smallpox, can immunize against most previously
deadly viruses, can kill most previously deadly bacteria. Theology has done nothing but talk of pestilence as
the wages of sin. Science can predict when a particular comet will reappear and, to the second, when the
next eclipse will appear. Science has put men on the moon and hurtled reconnaissance rockets around
Saturn and Jupiter. Science can tell you the age of a particular fossil and that the Turin Shroud is a medieval
fake. Science knows the precise DNA instructions of several viruses and will, in the lifetime of many present
readers, do the same for the human genome.
What has theology ever said that is of the smallest use to anybody? When has theology ever said anything
that is demonstrably true and is not obvious? I have listened to theologians, read them, debated against
them. I have never heard any of them ever say anything of the smallest use, anything that was not either
platitudinously obvious or downright false. If all the achievements of scientists were wiped out tomorrow,
there would be no doctors but witch doctors, no transport faster than horses, no computers, no printed books,
no agriculture beyond subsistence peasant farming. If all the achievements of theologians were wiped out
tomorrow, would anyone notice the smallest difference? Even the bad achievements of scientists, the bombs,
and sonar-guided whaling vessels work! The achievements of theologians don't do anything, don't affect
anything, don't mean anything. What makes anyone think that "theology" is a subject at all?
Where do the real dangers of genetic engineering lie?
by Richard Dawkins
Published in The London Evening Standard Aug 19 1998
Scare stories about genetic engineering may divert our attention from areas where we do need to be on our
guard against cynical exploiters
To listen to some people, you'd think genetically modified foods were radioactive. But genetic engineering is
not, of itself, either bad or good. It depends what you engineer. Doubtless a malevolent geneticist could stick
a poison gene into a potato. If we insert a gene for making oil of peppermint, we'll end up with peppermint
flavoured potatoes. It's up to us.
There's nothing new about genetic modification. That's precisely what Darwinian evolution is and it's
Darwinian evolution that put us all here. All plants and animals including humans, are genetically modified
versions of ancestors. Darwinian modifications are not designed; they evolve by natural selection - the
survival of the fittest - which may or may not be good from our point of view. Mosquitoes are genetically
modified by natural selection to eat humans, which is good for them and bad for us. Silkworms are genetically
modified by natural selection to make silk, which is good for them and also good for us because we steal the
Most genes are placed where they are by natural evolution. We can achieve a little further adjustment by
artifice, and here we at least have the opportunity to tailor changes that are good for us. We can selectively
breed - a kind of artificial version of Darwinian selection which we've been practising for thousands of years.
And we can genetically engineer. This is a technique that we're only just beginning to learn, and like all
novelty it arouses fear.
Genetically engineered plants have been sensation-ally called Frankenstein plants. But traditionally-bred
domestic peas are 10 times the volume of their wild ancestors. Does this make them Frankenstein peas? The
wild ancestors of corn cobs were half an inch long. Today a domestic cob may be one and a half feet long.
Yet nobody accuses our forebears of "playing God" when they bred them. Are spaniels and whippets
PR E S U M A B L Y selective breeding seems less sinister because it is a little older than genetic
engineering. But both techniques are extremely young compared with the long history of Darwinian genetic
modification that produced wild plants and animals in the first place. I am reminded of the old lady who
refused to enter an aeroplane, on the grounds that if God had meant us to fly He'd never have given us the
Both natural selection (which gave us the maize plant in the first place) and artificial selection (which
lengthened its cobs thirty-fold) depend upon random genetic error - mutation - and recombination, followed by
non-random survival. The difference is that in natural selection the fittest automatically survive. In artificial
selection we choose the survivors, and we may also arrange cunning hybridization regimes. In genetic
engineering we additionally exercise control over the mutations themselves. We do this either by directly
doctoring the genes, or by importing them from another species, sometimes a very distant species. This is
what "transgenic" means.
And now, here's a potential problem. Natural selection favours genes that have had plenty of time to get
adjusted to the other genes that are also being favoured in the species - the gene pool becomes a balanced
set of mutually compatible genes (I explain this in a chapter called The Selfish Cooperator in my forthcoming
book, Unweaving the Rainbow). One of the problems with artificial selection (partly because domestication is
so recent) is that the balance may be upset. Pekineses, bred to satisfy questionable human whims, have
consequent difficulties with their breathing. Bulldogs have trouble being born. Transgenic importation of
genes might raise even worse problems of this kind, because the genes come from a more distantly alien
genetic climate, and the translocation is even more recent. This is a danger we must think about.
Genetic engineering is a more powerful way to modify life than traditional artificial selection, so the potential
for danger is greater as well as the potential for good. Environmental dangers are likely to outweigh nutritional
ones, mainly because knock-on environmental effects are so complicated and hard to predict. But some risks
can be foreseen. Suppose there is an indiscriminate poison which is cheaper to produce than sophisticated
selective weedkillers, but which cannot be used because it kills the crop along with the weeds. Now suppose
a gene is introduced which makes wheat, say, completely immune to this particular herbicide.
FARMERS who sow the transgenic wheat can scatter the otherwise deadly poison with impunity, thereby
increasing their profits but with potentially disastrous effects on the environment. If the same company
patents both the poison and its genetic antidote, the monopolistic combination would be a nice little earner for
the company, while the rest of us would see it as a menace. On the other hand, enlightened genetic
engineers might achieve an exactly opposite effect, positively benefiting the environment by reducing the
quantity of weedkiller required. There is a choice.
Part of what we have to fear from genetic engineering is a paradox - it is too good at what it does. As ever,
science's formidable power makes correspond-ingly formidable demands on society's wisdom. The more
powerful the science, the greater the potential for evil as well as good. And the more important it is that we
make the right choices over how we use it. A major difficulty is political - deciding who is the "we" in that
sentence. If decisions over genetic engineering are left to the marketplace alone, the long-term interests of
the environment are unlikely to be well served. But that is true about so many aspects of life.
Hysterical damners of genetic engineering in all its forms are tactically inept, like the boy who cried wolf. They
distract attention from the real dangers that might follow from abusing the technology, and they therefore play
into the hands of cynical corporations eager to profit from such abuse.
Home Christine DeBlase-Ballstadt
Where d'you get those peepers
Dawkins, Richard, Where d'you get those peepers?., Vol. 8, New Statesman & Society, 06-16-1995, pp 29.
Creationist claims that organs like eyes are too complex to have evolved naturally are way wide of the mark,
says Richard Dawkins. In fact, eyes have evolved many times, often in little more than a blink of geological
Creationism has enduring appeal, and the reason is not far to seek. It is not, at least for most of the people I
encounter, because of a commitment to the literal truth of Genesis or some other tribal origin story. Rather, it
is that people discover for themselves the beauty and complexity of the living world and conclude that it
"obviously" must have been designed. Those creationists who recognise that Darwinian evolution provides at
least some sort of alternative to their scriptural theory often resort to a slightly more sophisticated objection.
They deny the possibility of evolutionary intermediates. "X must have been designed by a Creator," people
say, "because half an X would not work at all. All the parts of X must have been put together simultaneously;
they could not have evolved gradually."
Thus the creationist's favourite question "What is the use of half an eye?" Actually, this is a lightweight
question, a doddle to answer. Half an eye is just 1 per cent better than 49 per cent of an eye, which is already
better than 48 per cent, and the difference is significant. A more ponderous show of weight seems to lie
behind the inevitable supplementary: "Speaking as a physicist, I cannot believe that there has been enough
time for an organ as complicated as the eye to have evolved from nothing. Do you really think there has been
enough time?" Both questions stem from the Argument from Personal Incredulity. Audiences nevertheless
appreciate an answer, and I have usually fallen back on the sheer magnitude of geological time.
It now appears that the shattering enormity of geological time is a steam hammer to crack a peanut. A recent
study by a pair of Swedish scientists, Dan Nilson and Susanne Pelger, suggests that a ludicrously small
fraction of that time would have been plenty. When one says "the" eye, by the way, one implicitly means the
vertebrate eye, but serviceable image-forming eyes have evolved between 40 and 60 times, independently
from scratch, in many different invertebrate groups. Among these 40-plus independent evolutions, at least
nine distinct design principles have been discovered, including pinhole eyes, two kinds of camera-lens eyes,
curved-reflector ("satellite dish") eyes, and several kinds of compound eyes. Nilsson and Pelger have
concentrated on camera eyes with lenses, such as are well developed in vertebrates and octopuses.
How do you set about estimating the time required for a given amount of evolutionary change? We have to
find a unit to measure the size of each evolutionary step, and it is sensible to express it as a percentage
change in what is already there. Nilsson and Pelger used the number of successive changes of x per cent as
their unit for measuring changes of anatomical quantities.
Their task was to set up computer models of evolving eyes to answer two questions. The first was: is there a
smooth gradient of change, from flat skin to full camera eye, such that every intermediate is an improvement?
(Unlike human designers, natural selection can't go downhill not even if there is a tempting higher hill on the
other side of the valley.) Second, how long would the necessary quantity of evolutionary change take?
In their computer models, Nilsson and Pelger made no attempt to simulate the internal workings of cells.
They started their story after the invention of a single light-sensitive cell--it does no harm to call it a photocell.
It would be nice, in the future, to do another computer model, this time at the level of the inside of the cell. to
show how the first living photocell came into being by step-by-step modification of an earlier, more generalpurpose cell. But you have to start somewhere, and Nilsson and Pelger started after the invention of the
They worked at the level of tissues: the level of stuff made of cells rather than the level of individual cells.
Skin is a tissue, so is the lining of the intestine, so is muscle and liver. Tissues can change in various ways
under the influence of random mutation. Sheets of tissue can become larger or smaller in area. They can
become thicker or thinner. In the special case of transparent tissues like lens tissue, they can change the
refractive index (the light-bending power) of local parts of the tissue.
The beauty of simulating an eye, as distinct from, say, the leg of a running cheetah, is that its efficiency can
be easily mea-optics. The eye is represented as a two-dimensional cross-section, and the computer can
easily calculate its visual acuity, or spatial resolution, as a single real number. It would be much harder to
come up with an equivalent numerical expression for the efficacy of a cheetah's leg or backbone. Nilsson and
Pelger began with a flat retina atop a flat pigment layer and surmounted by a flat, protective transparent layer.
The transparent layer was allowed to undergo localised random mutations of its refractive index. They then
let the model deform itself at random, constrained only by the requirement that any change must be small
and must be an improvement on what went before.
The results were swift and decisive. A trajectory of steadily mounting acuity led unhesitatingly from the flat
beginning through a shallow indentation to a steadily deepening cup, as the shape of the model eye
deformed itself on the computer screen. The transparent layer thickened to fill the cup and smoothly bulged
its outer surface in a curve. And then, almost like a conjuring trick, a portion of this transparent filling
condensed into a local, spherical subregion of higher refractive index. Not uniformly higher, but a gradient of
refractive index such that the spherical region functioned as an excellent graded- index lens.
Graded-index lenses are unfamiliar to human lens-makers, but they are common in living eyes. Humans
make lenses by grinding glass to a particular shape. We make a compound lens. like the expensive violettinted lenses of modern cameras. by mounting several lenses together, but each one of those individual
lenses is made of uniform glass through its whole thickness. A graded-index lens, by contrast, has a
continuously varying refractive index with in its own substance. Typically, it has a high refractive index near
the centre of the lens. Fish eyes have graded-index lenses. Now it has long been known that, for a gradedindex lens, the most aberration-free results are obtained when you achieve a particular theoretical optimum
value for the ratio between the focal length of the lens and the radius. This ratio is called Mattiessen's ratio.
Nilsson and Pelger's computer model homed in unerringly on Mattiessen's ratio.
And so to the question of how long all this evolutionary change might have taken. In order to answer this,
Nilsson and Pelger had to make some assumptions about genetics in natural populations. They needed to
feed their model plausible values of quantities such as "heritability" . Heritability is a measure of how far
variation is governed by heredity. The favoured way of measuring it is to see how much monozygotic (that is,
"identical") twins resemble each other compared with ordinary twins. One study found the heritability of leg
length in male humans to be 77 per cent. A heritability of too per cent would mean that you could measure
one identical twin's leg to obtain perfect knowledge of the other twin's leg length, even if the twins were
reared apart. A heritability of 0 per cent would mean that the legs of monozygotic twins are no more similar to
each other than to the legs of random members of a specified population in a given environment. Some other
heritabilities measured for humans are 95 per cent for head breadth, 85 per cent for sitting height. 80 percent
for arm length and 79 per cent for stature.
Heritabilities are frequently more than 50 percent, and Nilsson and Pelger therefore felt safe in plugging a
heritability of 50 per cent into their eye model. This was a conservative, or "pessimistic", assumption.
Compared with a more realistic assumption of, say, 70 per cent, a pessimistic assumption tends to increase
their final estimate of the time taken for the eye to evolve. They wanted to err on the side of overestimation
because we are intuitively skeptical of short estimates of the time taken to evolve something as complicated
as an eye.
For the same reason, they chose pessimistic values for the coefficient of variation (that is, for how much
variation there typically is in the population) and the intensity of selection (the amount of survival advantage
improved eyesight confers). They even went so far as to assume that any new generation differed in only one
part of the eye at a time: simultaneous changes in different parts of the eye, which would have greatly
speeded up evolution, were outlawed. But even with these conservative assumptions, the time taken to
evolve a fish eye from fiat skin was minuscule: fewer than 400,000 generations. For the kinds of small
animals we are talking about, we can assume one generation per year, so it seems that it would take less
than half a million years to evolve a good camera eye.
In the light of Nilsson and Pelger's results, it is no wonder "the" eye has evolved at least 40 times
independently around the animal kingdom. There has been enough time for it to evolve from scratch 1,500
times in succession within any one lineage. Assuming typical generation lengths for small animals, the time
needed for the evolution of the eye, far from stretching credulity with its vastness, turns out to be too short for
geologists to measure! It is a geological blink.