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The story goes that when they were first contacted by Europeans, a
small stone-age tribe in Africa called the Dogon knew about a string
of astronomical phenomena, including Jovian satellites, the rings of
Saturn and the invisible companion star of Sirius ("The Pup"). Some
UFO enthusiasts have taken this as proof of visits to the Dogon by
aliens.
In "Broca's Brain", Carl Sagan writes:
The most striking aspects of Dogon astronomy have been recounted
by Marcel Griaule, a French anthropologist working in the 1930s
and 1940s. While there is no reason to doubt Griaule's account,
it is important to note that there is no earlier Western record of
these remarkable Dogon folk beliefs [...]
The facts known to the Dogon were mostly discovered over a century
before Griaule discovered them. It is most likely that the Dogon got
this knowledge from human visitors rather than extra-terrestrial ones.
In addition their astronomy included a number of facts which were
widely accepted in the 1920s but which are now known to be false. It
seems odd that visiting aliens would have made the same mistakes.
Apparently a debunking of Dogon astronomy can be found in an
article by W. Van Beck in _Current Anthropology_, vol. 32, pp.
139-167, 1991.
Faith Healing and Alternative Therapies
=======================================
Disclaimer: I am not medically qualified. If you have a medical
problem then I strongly recommend that you go to a
qualified medical practitioner. Asking the Net for
specific medical advice is always a bad idea.
4.1: Isn't western medicine reductionistic and alternatives holistic?
---------------------------------------------------------------------
Practitioners of alternative therapies often put forward the idea that
modern scientific medicine is reductionistic: it concentrates on those
parts of the body that are not working properly, and in so doing it
reduces the patient to a collection of organs. Alternative therapies
try to consider the patient as a whole (a holistic approach).
This is a fine piece of rhetoric, but it's wrong. It is true that
modern medicine looks at the details of diseases, trying to find out
exactly what is going wrong and what is causing it. But it also looks
at the life of the patient, and tries to understand how the patient
interacts with his/her environment and how this interaction can be
improved. For instance, smoking is known to cause a wide variety of
medical problems. Hence doctors advise patients to give up smoking as
well as treating the individual illnesses that it causes. When a
patient presents with an illness then the doctor will not only treat
the illness but also try to understand how this illness was caused in
order to avoid a recurrence.
4.2: What is a double-blind trial? What is a placebo?
------------------------------------------------------
A double-blind trial is the standard method for deciding whether or
not a treatment has any "real" effect.
A placebo is a "treatment" that has no effect except through the mind
of the patient. The usual form is a pill containing a little lactose
(milk-sugar), although a bitter-tasting liquid or injections of 1cc
saline can be used instead.
The "placebo effect" is the observed tendency for patients to display
the symptoms they are told to expect.
The problem is that the state of mind of a patient is often a
significant factor in the effect of a course of treatment. All
doctors know this; it is why "bedside manner" is considered so
important. In statistical tests of new treatments it is even more
important, since even a small effect from the state of mind of a small
fraction of the patients in the trial can have a significant effect
on the results. Hence new medicines are tested against a placebo.
The patients in the trial are randomly divided into two groups. One
of these groups is given the real medicine, the other is given the
placebo. Neither group knows which they have been given. Hence the
state of mind for both groups will be similar, and any difference
between the two groups must be due to the drug. This is a blind trial.
It has been found that patients can be unconsciously affected by the
attitude and expectations of the doctor supplying the drug, even if
the doctor does not explicitly tell them what to expect. Hence it is
usual for the doctor to be equally unaware which group is which. This
is a "double blind" trial. The job of remembering which group is
which is given to some administrative person who does not normally
come into contact with patients.
This causes problems for many alternative therapies because they do
something to the patient which is difficult to do in a placebo-like
manner. For instance, a treatment involving the laying-on of hands
cannot be done in such a way that both patient and practitioner are
unaware as to whether a "real" laying on of hands has taken place.
There are partial solutions to this. For instance one study employed
a three-way test of drug placebo, counseling and alternative therapy.
4.3: Why should scientific criteria apply to alternative therapies?
-------------------------------------------------------------------
So that we can tell if they work or not. If you take a patient
and give them treatment then one of three things will happen: the
patient will get better, will get worse, or will not change. And this
is true whether the treatment is a course of drugs chosen by a doctor,
an alternative therapy, or just counting to ten.
Many alternative therapies depend on "anecdotal evidence" where
particular cases got better after the therapy was applied. Almost any
therapy will have some such cases, even if it actually harms the
patients. And so anecdotal evidence of Mrs. X who was cured of cancer
by this wonderful new treatment is not useful in deciding whether the
treatment is any good.
The only way to tell for sure whether or not an alternative treatment
works is to use a double-blind trial, or as near to it as you can get.
See the previous question.
4.4: What is homeopathy?
------------------------
Homeopathy is sometimes confused with herbalism. A herbalist
prescribes herbs with known medicinal effects. Two well known
examples are foxglove flowers (which contain digitalin) and willow
bark (which contains aspirin). Folk remedies are now being studied
extensively in order to winnow the wheat from the chaff.
Homeopathists believe that if a drug produces symptoms similar to
certain disease then a highly diluted form of the same drug will cure
the disease. The greater the dilution, the stronger this curative
effect will be (this is known as the law of Arndt-Schulz). Great
importance is also attached to the way in which the diluted solution
is shaken during the dilution.
People are skeptical about homeopathy because:
1: There is no known mechanism by which it can work. Many homeopathic
treatments are so diluted that not one molecule of the original
substance is contained in the final dose.
2: The indicator symptoms are highly subjective. Some substances have
hundreds of trivial indicators.
3: Almost no clinical tests have been done.
4: It is not clear why trace impurities in the dilutants are not also
fortified by the dilution mechanism.
Although homeopathy involves little more than doing nothing, it was
invented in the days when doing nothing was usually better for the
patient than conventional treatment. It therefore represented a
significant advance in medical practice. Since then conventional
medicine has improved beyond recognition, while homeopathy is still
equivalent to doing nothing.
Reports of one scientific trial that seemed to provide evidence for
homeopathy until a double-blind trial was set up can be found in
Nature vol 333, p.816 and further, and the few issues of Nature
following that, about until November of that year (1988).
SI ran a good article on the origins and claims of homeopathy:
Stephen Barrett, M.D., "Homeopathy: Is It Medicine?", SI,
vol. 12, no. 1, Fall 1987, pp. 56-62.
4.5: What is aromatherapy?
--------------------------
A belief that the essential oils of various flowers have therapeutic
effects. These effects are psychological rather than physical, and so
its a bit difficult to define what we mean by a statement that "it
works". After all, if people do it and feel better then that is a
real effect, whether it occurred because of suggestion or because the
flowers contain a powerful psychoactive drug.
4.6: What is reflexology? What is iridology?
---------------------------------------------
Reflexology is an alternative therapy based on massage of the feet.
The idea is that parts of the body can be mapped onto areas of the
feet. There is no known mechanism by which massaging the feet can
affect other parts of the body (other than the simple soothing and
relaxing effect that any massage gives) and no evidence that it
actually works.
Iridology is a remarkably similar notion. Diseases are detected and
diagnosed by examining the iris of the eye. A good critique of
iridology: Russell S. Worrall, "Iridology: Diagnosis or Delusion?",
SI, vol. 7 no. 3, pp. 23-35.
4.7: Does acupuncture work?
----------------------------
There is evidence that acupuncture treatment has an analgesic ("pain
killing") effect. The mechanism seems to involve the endogenous
opiate system (at least in part), but the exact mechanism by which
endogenous opiates are released by acupuncture skin stimulation is not
yet known. It does not appear that the effect can be explained simply
by pain caused by the needles. However it is possible to achieve
similar effects by suggestion alone, suggesting that acupuncture is no
more than a placebo.
There have been reports of measurable physiological effects,
apparently via local changes in the activity of the sympathetic and
parasympathetic nervous systems. While much more detail remains to be
elucidated, this is at least a testable hypothesis which brings
acupuncture within the realm of science.
This suggests that acupuncture might be a useful tool in pain
management, but that it is unlikely to be of value in curing the
underlying cause of the pain.
The traditional theory of acupuncture involves balancing the yin and
yang (male and female principles) which flow in pathways through the
body. Nothing bearing any resemblance to this has been found by
medical researchers.
References:
Skrabanek, Petr: Acupuncture: Past, Present and Future. In: Examining
Holistic Medicine by Stalker D & Glymour G (eds), Prometheus Books, NY
Skrabanek, Petr: Acupuncture and Endorphins. Lancet 1984;i:220
Skrabanek, Petr: Acupuncture and the Age of Unreason. Lancet
1984;i:1169-1171
Skrabanek, Petr: Acupuncture-Needless Needles. Irish Medical
Journal1986;79:334-335
A 1977 study, Stern, Brown, Ulett, and Sletten, 'A comparison of
hypnosis, acupuncture, morphine, Valium, aspirin, and placebo in the
management of experimentally induced pain,' Annals_of_the_New_York_
Academy_of_Sciences, 296, 175-193, found that acupuncture,
morphine, and hypnostic analgesia all produced significantly reduced
pain ratings for cold pressor and ischemic pain.
Mayer,Price, Raffi, 1977,
"Antagonism of acupuncture analgesia in man by the narcotic
antagonist naloxone," _Brain_Research_, 121, 368-372.
Sjolund, Terenius, Erikson, 1977,
"Increased cerebrospinal fluid levels of endorphins after electroacupuncture,"
Acta_Physiologica_Scandinavica, 100, 382-384.
"Practical application of acupuncture analgesia" and it's by Cheng,
SB (1973 Apr 27), _Nature 242(5400)_: 559-60.
"Electrophysiological measures during acupuncture-induced surgical
analgesia" by Starr A (1989 Sep) _Arch Neurol 46(9)_: 1010-12.
4.8: What about psychic surgery?
--------------------------------
Psychic surgeons have claimed to be able to make magical incisions,
remove cancers and perform other miracles. To date, no investigation
of a psychic surgeon has ever found real paranormal ability. Instead
they have found one of two things:
1: Simple conjuring tricks. The "surgeons" in these cases are
confidence tricksters who prey on the desperate and the foolish.
2: Delusions of grandeur. These people are even more dangerous than
the first category, as their treatments may actually cause harm in
addition to whatever was wrong with the patient in the first
place.
4.9: What is Crystal Healing?
-----------------------------
The belief that carrying a small quartz crystal will make you a
healthier person. People selling these crystals use phrases like "the
body's natural energy fields" and "tuning into the right vibrational
frequencies". All this sounds vaguely scientific but means absolutely
nothing. Crystal Healing is mostly a New Age idea. See the section
on the New Age below for more information.
4.10: Does religious healing work?
----------------------------------
Miraculous healing is often put forward as a proof of the existence
and approval of God. The Catholic and Christian Scientist churches in
particular often claim that believers have been healed, but none of
these healings have stood up to careful scrutiny. However it should
be noted that the Catholic church does investigate alleged miracles.
One famous "healing" which has been carefully investigated is the case
of Mrs. Jean Neil. Many people have seen the video of her getting out
of a wheel-chair and running around the stadium at meeting led by the
German evangelist Reinhard Bonnke. This was investigated by Dr. Peter
May, a GP and member of the General Synod of the Church of England.
His findings were reported in the Skeptic (organ of the UK Skeptics).
Here is a summary of the report. [Any errors are mine. PAJ].
May found that Mrs. Neil was helpful and enthusiastic when he
contacted her, and there is little doubt that her quality of life has
improved greatly since the "healing". However May was unable to find
any physical changes. His report lists each of the illnesses claimed
by Mrs. Neil, and he found that they were either not recorded by
doctors previous to the healing or that no physical change had taken
place. It seems that the only change in Mrs. Neil was in her mental
state. Before the healing she was depressed and introverted.
Afterwards she became happy and outgoing.
A more sinister aspect of the story is the presentation of the Neil
case in a video promoted by CfaN Productions. This represented Mrs.
Neil before the healing as a "hopeless case", implied that she had a
single serious illness rather than a series of less major ones, and
included the false statement that she had been confined to a
wheelchair for 25 years (in fact Mrs. Neil had used a wheelchair for
about 15 months and could still walk, although with great difficulty).
A report on her spine was carefully edited to include statements about
her new pain-free movement but to exclude the statement that there was
no evidence of physical changes.
For the full report, see "The Skeptic" p9, vol. 5, no. 5, Sept. 91. Back
issues are available from "The Skeptic (Dept. B), P.O. Box 475,
Manchester, M60 2TH, U.K. Price UKL 2.10 for UK, UKL 2.70 elsewhere.
The video is entitled "Something to Shout About --- The Documentation
of a Miracle". Presumably "CfaN Productions" is part of Bonke's
organisation "Christ for all Nations" [does anyone have an address?]
Of course, this does not disprove the existence of miraculous healing.
Even Mrs. Neil's improvement could have been due to divine
intervention rather than a sub-conscious decision to get better (as
most skeptics would conclude, although the May report carefully
refrains from doing so). I include this summary here because the Neil
case is often cited by evangelical Christians as an undeniable
miracle. In fact the case demonstrates that even such dramatic events
as a cripple getting up and running may not be so very inexplicable.
For more general coverage of this topic, see James Randi's book "The
Faith Healers". Free Inquiry magazine has also run exposes on
fraudulent faith healers like Peter Popoff and W.V. Grant.
4.11: What harm does it do anyway?
----------------------------------
People have died when alternative practitioners told them to stop
taking conventional treatment. Children have died when their parents
refused to give them conventional treatment. These issues matter.
Most alternative treatments are harmless, so the "complementary
medicine" approach where conventional and alternative therapies
proceed in parallel will not hurt anyone physically (although it is a
waste of time and money).
Creation versus Evolution
=========================
5.1: Is the Bible evidence of anything?
---------------------------------------
Apart from the beliefs of those who wrote it, no. It is true that
most Christians take the truth of at least some parts of the bible as
an article of faith, but non-Christians are not so constrained.
Quoting the bible to such a person as "evidence" will simply cause
them to question the accuracy of the bible. See the talk.atheism FAQ
lists for more details.
Some things in the bible are demonstrably true, but this does not make
the bible evidence, since there are also things in the bible that are
demonstrably false.
5.2: Could the Universe have been created old?
----------------------------------------------
An argument is sometimes put forward along the following lines:
We know from biblical evidence (see above) that the Universe
is about 6,000 years old. Therefore God created it 6,000
years ago with fossils in the ground and light on its way from
distant stars, so that there is no way of telling the real age
of the Universe simply by looking at it.
This is the "Omphalos" (Navel) theory of Edmund Gosse. Adam had no
mother so did not need a navel, but was created by God with one, i.e.
physical proof of connection with a nonexistent mother. Similarly, at
the moment of Creation the world was chock-full of things that must
have happened yesterday, when yesterday did not exist.
The hypothesis is unfalsifiable, and therefore not a scientific one
(see the section on the scientific method). It could also be made for
any date in the past (like last Tuesday). Finally it requires that
God, who is alleged to speak to us through His Works, should be lying
to us by setting up a misleading Creation. This seems to be rather
inconsistent with Biblical claims of God being the source of all
truth.
One might also argue that in creating the universe "old", God also
created the past of the universe. This "fake" past must be a perfect
match with the "real" past (otherwise we could spot the join). Hence
the events from before the moment of "creation" are just as real as
the events which have happened since. Since God is supposed to exist
independently of time and space, this makes the whole idea
meaningless.
Note that this argument is not put forward by creation scientists.
They hold that modern science has misinterpreted the evidence about
the age of the universe.
5.3: What about Carbon-14 dating?
---------------------------------
Isotope dating takes advantage of the fact that radioactive materials
break down at a rate independent of their environment. Any solid
object that formed containing radioactive materials therefore steadily
loses them to decay. If it is possible to compare the amount of
radioactive material currently present with the amount originally
present, one can deduce how long ago the object was formed. The amount
originally present cannot, of course, be observed directly, but can be
determined by indirect means, such as identifying the decay products.
C-14 dating uses an unstable isotope of carbon that is constantly
being produced in the upper atmosphere by cosmic rays. This process is
assumed to be in equilibrium with the decay of C-14 throughout the
biosphere, so the proportion of carbon that is C-14 as opposed to the
stable C-12 and C-13 isotopes is essentially constant in any living
organism. When an organism dies, it stops taking up new carbon from
its environment, but the C-14 in its body continues to decay. By
measuring the amount of C-14 left in organic remains, one can
establish how long ago the organism they came from died. Because C-14
has a half-life of only a few thousand years, C-14 dating can only be
used for remains less than a few tens of thousands of years old--
after that, the C-14 is entirely gone, to all practical purposes.
Other isotopic dating techniques, such as potassium-argon dating, use
much longer-lived radionuclides and can reliably measure dates
billions of years in the past.
Actually the production rate isn't all that constant, so the amount of
C-14 in the biosphere varies somewhat with time. You also need to be
sure that the only source of carbon for the organism was atmospheric
carbon (via plants). The nominal date from a C-14 reading, based on
the present concentration, therefore has to be corrected to get the
real date --- but once the correction has been calculated using an
independent dating tool like dendrochronology (see below), it can be
applied to almost any sample.
There are some known anomalies in C14 dating, such as molluscs that
get their carbon from water. Creationists seem to make a habit of
taking samples that are known to be useless for C14 dating, presenting
them to scientists for examination, representing them as other than
they are, and then claiming the anomalous dates they get for them as
evidence that C14 dating is all a sham.
While it is true that there *may* be unknown errors in some dating
methods (see the note in section 0 about science "proving" things)
this assertion cannot be used to write off isotope dating as evidence
of an ancient Earth. This is because:
o There are several independent ways of dating objects, including
radio-isotopes, dendrochronology, position in rock strata etc.
These all give a consistent picture.
o Dating methods all point to an *old* Earth, about *half a million*
times older than the Creationists claim. This requires dating
methods which are accurate up to 6,000 years ago and then suddenly
start to give completely wrong (but still consistent) answers. Even
if our dating methods are out by a factor of 10 or 100, the earth is
still thousands of times older than Creationists claim.
5.4: What is dendrochronology?
------------------------------
The science of dating wood by a study of annual rings.
[These figures and references come from a longer summary e-mailed to me
by . Any mistakes are mine. PAJ]
Everyone knows that when you cut down a tree the cut surface shows a
series of concentric rings, and that one of these rings is added each
year as the tree grows. The lighter part of the ring is the summer
growth and the darker part is the winter growth. Hence you can date a
tree by counting the rings.
But the rings are not evenly spaced. Some rings are wider than
others. These correspond to good and poor growing seasons. So if you
have a piece of wood cut down a few thousand years ago, you can date
it by comparing the pattern of rings in your sample to known patterns
in recently cut trees (Bristlecone pines exist which are over 4600
years old, and core samples allow ring counting without killing the
tree).
Now for the clever bit. The tree from which your sample came may have
been old before any trees now alive were even saplings. So you can
extend the known pattern of rings back even further, and hence date
samples of wood which are even older. By lining up samples of wood in
this way, dendrochronologists have been able to produce a continuous
pattern of rings going back around 9,900 years. This easily refutes
the chronology of Bishop Usher, who calculated from dates and ages
given in the Bible that the Earth was created in 4004 BC.
Dendrochronology is also valuable in providing calibration data for
C14 and other isotope dating methods. See the previous question for
more details.
References:
"Dendrochronology of the Bristlecone Pine....."
by C. W. Ferguson, 1970. Published in a book called
"Radiocarbon Variations and Absolute Chronology"
This takes the record back 7484 years. More recently there is
Bernd Becker, Bernd Kromer & Peter Timborn
"A stable-isotope tree-ring timescale of the Late
Glacial/Holocene boundary"
Nature 353 (1991) pp. 647-649
The authors have "established a 9,928 year absolute dated
dendrochronological record of Holocene oak." Actually, their timescale goes
even further back, because by overlap with a pine tree sequence they date
the end of the Late Glacial at a minimum age op 10,970 BP.
5.5: What is evolution? Where can I find out more?
---------------------------------------------------
Many creationist "refutations" of evolution are based on a straw-man
argument. The technique is to misrepresent the theory of evolution,
putting forward an absurd theory as "what scientists claim". The
absurdity of this pseudo-evolution theory is then ridiculed.
* Debunking all these refutations would take a lot of space. Instead I
suggest that anyone interested should go and read the FAQ lists over
on talk.origins. These contain good explanations of what evolution is
(and isn't). The talk.origins Welcome FAQ is posted every 14 days to
news.answers and talk.answers. It contains instructions for FTPing
the other FAQs.
* Books and essays on the subject by Stephen Jay Gould are good, and
"The Blind Watchmaker" by Richard Dawkins is the sort of book that
makes you want to find a creationist to argue with.
Also see "Darwinism Defended: a guide to the Evolution Controversies"
by Michael Ruse (Addison-Wesley, 1982).
* A. Strahler, _Science and Earth History_ (1987, Prometheus Books,
ISBN 0-87975-414-1, 552 pp).
Strahler's book is heavily referenced, thoroughly indexed, and covers
most of the common creationist arguments. There are only a handful
of books explicitly aimed at addressing creationist claims, and this
one is the best of the lot. NCSE sells Strahler's book for $47.95
($38.55 for members).
* The NCSE is the only national (American) anti-creationism organization.
NCSE is affiliated with the AAAS (American Association for the
Advancement of Science -- publishers of the journal _Science_) and
NSTA (National Science Teacher's Association). The organization is
mainly aimed at negating creationists' efforts to get into public
school science classes.
There are no membership requirements. Membership costs $25 per year
($32 foreign, $39 foreign air delivery). All members receive the
quarterly newsletter _NCSE Reports_ and the semi-annual _Creation/
Evolution Journal_, as well as discounts from their book ordering
service. NCSE sells a decent selection of books, taped speeches and
debates, and other relevant material.
NCSE (National Center for Science Education)
P.O. Box 9477 / Berkeley, CA 94709
(510) 526-1674
5.6: "The second law of thermodynamics says....
-----------------------------------------------
...that entropy is always increasing. Entropy is a measure of the
randomness in a system. So the universe is getting more and more
disordered. But if this is so, how can life happen, since
evolutionists claim essentially that life is a system that becomes
more ordered with time?"
[ The following answer was kindly contributed by
Dr. Roydon A. Fraser, Associate Professor,
University of Waterloo, Waterloo, Ontario, CANADA.
email . ]
This line of reasoning would be valid if it were not for the simple
fact that the above is a misstatement of the second law of
thermodynamics. A correct statement reads,
"The second law of thermodynamics states that the net entropy
within an ISOLATED system is always increasing or remains
constant."
An isolated system is one that does not undergo a change of state due to
external work or heat transfer. The entropy in an isolated system in
equilibrium is constant at its maximum value.
The major key here to demonstrating that life on earth does not
violate the second law is to realize that the earth is a NON-isolated
system. The earth is continuously absorbing radiative heat transfer
energy from the sun and continuously transferring thermal energy to
outer-space through thermal emissions. Because the earth participates
in these heat transfer processes it is non-isolated.
For instance, when you freeze water the molecules of H2O line up in
beautifully organised crystals. This organisation does not violate
the second law of thermodynamics because the work done by the freezer
in extracting the heat from the water has caused the total entropy of
the *universe* to rise, even though the entropy of the *water* has
decreased.
Similarly the existence of life on earth has not decreased the entropy
of the universe, so the second law has not been violated.
From a classical thermodynamics perspective the universe as a whole is
isolated, and hence, the net entropy (disorder) of the universe
continues to increase (the situation where the universe's entropy
remains constant does not exist because we live in a universe with
friction).
The second law states that the entropy of the sun plus the earth's
entropy plus the entropy of outer-space (i.e, the net entropy) cannot
decrease. It is completely acceptable for the entropy of the earth to
decrease provided the net entropy of the sun and outer-space
increases. As an analogy consider the freezing of water into ice.
The entropy of ice is less than that of water because ice molecules
are more organized (they are in a crystal lattice) than water
molecules (which move about randomly). That is, the water's entropy
has decreased, but only at the expense of increasing the
entropy in the room and at the expense of a net increase in the
universe's entropy (i.e., by the second law the entropy increase in
the room must be equal to or be greater than the entropy decrease
experienced by the water).
It is interesting to observe that an enormous amount of entropy
production is actually associated with the formation of life on earth.
According to Plank (father of quantum mechanics) the entropy flow from
the sun is proportional to the reciprocal of the sun's temperature.
More precisely it is four thirds times the heat transfer from the sun
all divided by the temperature of the sun (about 6000 kelvin). By the
law of conservation of energy (and ignoring global warming) the heat
flow from the sun to the earth is equal to the thermal radiative heat
transfer from the earth to outer-space. The entropy flow from the
earth is therefore four thirds times the heat transfer from the sun
all divided by the temperature of the earth as seen from outer-space
(about 300 kelvin = 27 celsius). Therefore, the entropy flow from the
earth is greater than the entropy flow to the earth which means that
entropy has been produced on earth (via friction, etc.).
In conclusion the existence of life on earth does not violate the
second law of thermodynamics.
5.7: How could living organisms arise "by chance"?
--------------------------------------------------
This is actually a less sophisticated version of the question above.
Consider freezing water as an example. The wonderful arrangement
in crystals arises from the random movement of water molecules. But
ice crystals do not require divine intervention as an explanation, and
neither does the evolution of life.
Also, consider a casino. An honest casino makes a profit from
roulette wheels. The result of a spin of a particular wheel is purely
random, but casinos make very predictable profits. So in evolutionary
theory, even though the occurrence of a particular mutation is random,
the overall effect of improved adaptation to the environment over time
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