Scientific Evidence

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Scientific Evidence for God
The Design of Living
Things
God and Evolution
Prof. Rob Koons
Leadership for America
Detecting Design
Old Man of the Mountain, New Hampshire
Mount Rushmore, South Dakota
Dawkins R. 1986. The Blind
Watchmaker. New York: Norton, p. 1
• “Biology is the study of complicated
things that give the appearance of
having been designed for a
purpose.”
Dawkins R. 1986. The Blind
Watchmaker. New York: Norton, p. 21
• “We may say that a living body or organ is well
designed if it has attributes that an intelligent and
knowledgeable engineer might have built into it in
order to achieve some sensible purpose, such as
flying, swimming, seeing … [A]ny engineer can
recognize an object that has been designed, even
poorly designed, for a purpose, and he can usually
work out what that purpose is just by looking at the
structure of the object.”
Dawkins R. 1986. The Blind
Watchmaker. New York: Norton, p. 21
• “Yet the living results of natural
selection overwhelmingly impress us
with the appearance of design as if by
a master watchmaker, impress us with
the illusion of design and planning.”
Charles Darwin, On the Origin of Species, p. 158
• If it could be demonstrated
that any complex organ
existed which could not
possibly have been formed by
numerous, successive,
slight modifications, my
theory would absolutely break
down. But I can find out no
such case.
Irreducible
Complexity
Irreducible Complexity
• A function is “irreducibly complex” (Michael
Behe) if it is realized by a large number of subcomponent processes, each of which must be
carefully adjusted to the others, and all of which are
necessary if the whole system is to serve its
characteristic function at all.
• Examples: a clock, a mousetrap, the Space Shuttle, an
enzyme, a molecular “machine” (like the flagellum
of bacteria).
The Bacterial Flagellum
Voet & Voet,
1995
Problem for Darwinism
• “We should reject, as a matter of principle, the
substitution of intelligent design for the dialogue of
chance and necessity (Behe 1996); but we must
concede that there are presently no detailed
Darwinian accounts of the evolution of any
biochemical system, only a variety of wishful
speculations.” Franklin Harold (2001).
Cell (1998) 92, table of contents.
• The Cell as a Collection of Protein Machines: Preparing the
Next Generation of Molecular Biologists, Bruce Alberts
• Polymerases and the Replisome: Machines within Machines,
Tania A Baker and Stephen P Bell
• Eukaryotic Transcription: An Interlaced Network of
Transcription Factors and Chromatin-Modifying Machines,
James T Kadonaga
• Mechanical Devices of the Spliceosome: Motors, Clocks,
Springs, and Things, Jonathan P Staley and Christine Guthrie
• Molecular Movement inside the Translational Engine,
Kevin S Wilson and Harry F Noller
• The Hsp70 and Hsp60 Chaperone Machines,
Bernd Bukau and Arthur L Horwich
The Origin of Life
•
•
•
Very rapid: within 10 million years of
liquid water on Earth’s surface.
Couldn’t be the result of a lucky series
of coincidences.
Smallest self-replicator requires 300
genes, 100,000 base pairs.
Convinced famous atheist philosopher
Anthony Flew.
There is a God: How the World’s Most
Notorious Atheist Changed His Mind
(2007)
• “Can the origins of a system of coded
chemistry be explained in a way that
makes no appeal whatever to the kinds
of facts that we otherwise invoke to
explain codes and languages, systems
of communication, the impress of
ordinary words on the world of matter?”
Functional Proteins
• The vast majority of randomly generated proteins do
not fold in a stable way at all, and so cannot function
as enzymes. Let’s call these non-functional proteins.
• Estimate of the ratio of functional to non-functional
proteins (with 300 amino acids): 1 in 10267. Compare:
the number of grains of sand in Sahara (1030); the
number of atoms in the universe (1080).
The problem for Undirected Evolution
• This means that evolution cannot take us from one
functional protein to the next by a series of small,
unplanned steps, since the path between two
functional proteins must cross a huge number of
non-functional intermediaries.
• Somehow, these supposedly random mutations
must make the leap from one functional island to
another, across a vast ocean of non-functional
space.
The origin of the genetic code.
• One of the greatest weaknesses of the Darwinian
idea is that it cannot be extended to the
explanation of the origin of life, and in particular,
the origin of the genetic code itself.
• The genetic code is itself an amazing piece of
irreducibly complex machinery: out of every
million randomly generated codes, only one is
likely to be as error-resistant as is our actual code
(Hurst, Freeland).
New discoveries
• There is very little, if any, “junk DNA”: almost all
of the DNA molecule has some function.
• Genes are not isolated -- in fact, genes overlap
each other. The very same segment of DNA could
belong to several genes at once, being read from
“left to right”, or “right to left”, and with different
starting and stopping points. The DNA molecule is
less like a novel and more like a crossword puzzle.
Multiple, Overlapping Transcripts
transcripts
“Gene” 2
“Gene” 1
“Gene” 4
“Gene” 3
“Gene” 5
Problems for Undirected Darwinism
•
•
Each mutation now has an effect,
simultaneously, on thousands of products.
Since harmful effects are much more likely
than beneficial ones, the odds that any
mutation could be beneficial become
incredibly long. (Chung, W.-Y et al., 2007)
Evolution and Creation
•
•
•
Are they compatible? Yes.
God could have used ‘evolution’ to
create life: (1) gradual ‘unfolding’ of
new forms of life over billions of years,
(2) common ancestors for all living
forms.
God could have used ‘random’
mutations (with occasional nudges) to
generate the forms of life He intended.
However…
• None of this makes the evidence from
biological function to design at all doubtful,
since we have compelling reason to reject
“blind chance” as the cause of complex
adaptations.
• Even if God front-loaded the design into the
chemistry and geology of the world, this still
requires intelligence.
What is “Intelligent Design”?
•
•
•
•
•
What it’s not:
Not an alternative to evolution (descent
with modifications).
Not an alternative to natural selection.
Not a matter of religious faith.
Not, at this point, a scientific theory.
The ID/Darwinism Debate
•
•
•
Neither Darwinism nor ID are scientific
theories: both are metaphysical
frameworks.
We can ask which framework is most
reasonable as a way of making sense of
the phenomena of nature.
A philosophical, rather than a scientific,
question.
The Central Issue
• Intelligent design can be defined as an
approach to biological origins that rejects one of
the core commitments of the Darwinian
paradigm, namely:
– The thesis that new modifications (by mutation,
change in gene expression or otherwise) occur with a
probability that is independent of their current or future
contribution to biological function.
The Blind Chance Thesis
•
•
•
Let’s call this core Darwinian
presupposition the “blind chance thesis”.
Is the truth of the chance thesis a
scientific question?
No, it is a question of fundamental
metaphysics that concerns the form of
future biological theory.
Methodological Naturalism
According to MN, it is part of the very
definition of science that it make no appeal
to “supernatural” agencies or miracles:
• The supernatural cannot be included in
the “data base”.
• No proposed theory can include
reference to God or other supernatural
agents.
• The “evidence base” (anything used to
evaluate theories for their plausibility or
viability) must be at least agnostic about
God.
Is Science Based on MN a defeater for
belief in God?
No, because if a scientific program adopts a
method that excludes the very idea of divine
agency from the outset, the fact that it doesn’t later
discover any need for God’s agency is totally
predictable, no evidence against God whatsoever.
In order to determine whether biology provides
evidence for (or against) God, we must suspend
Methodological Naturalism and put divine agency
back on the table.
Objection: Science can refer only to
physical causes
•
•
Historically, this is false. Many scientists
in the past have postulated non-physical
forces (chemical, biological, psychic).
Not clear what “physical” means here.
When Newton introduced gravity,this was
rejected as an “occult force”.
Intelligent Design in nature = natural
teleology
• Teleology comes from the Greek word “telos”
for end or purpose.
• Historically, teleology has played an important
role in the development of science, including
biology.
• In the mid-19th century, the philosophical
movement of “materialism” (also called
“physicalism”) began to emerge.
Can science refer only to physical
causes?
• The progress of science has not been identical
to the progress of materialism.
• Ancient materialism was a scientific dead end.
• Theism, the idea that the natural universe is an
artifact, played a crucial role in the scientific
revolution, as documented by Duhem, Jaki and
others.
Can science refer only to physical
causes?
•
•
•
The very idea of a law of nature is a nonphysical cause.
First introduced by a Christian theologian,
Basil of Caesarea.
In the early modern era -- Kepler,
Newton, Boyle -- retained its core,
theological meaning.
Can science refer only to physical
causes?
• The ancient atomists believed this, and for this
reason, they rejected the search for laws of
nature and the use of mathematics in science.
• The introduction of mathematics to science (by
Ptolemy, Roger Bacon, da Vinci, Galileo, Kepler,
Newton) presupposed a non-materialist
philosophy.
Can science refer only to physical
causes?
•
•
By restricting science to physical causes
only, this philosophy introduces the
possibility of scientific blindspots.
When MN-based science reports that
God is not indicated by the evidence, this
is no surprise – His agency has been
excluded from the inquiry at the outset.
Is Darwinism testable?
• The core commitment of Darwinism, the Chance
Thesis, is not falsifiable or testable.
• It is always possible that all the past
modification involved in evolutionary history
occurred with a function-blind, chemicallydetermined probability.
• Even if a particular system seems to be
irreducibly complex, it is impossible to prove that
there is no Darwinian path to it.
Is the Blind Chance Thesis a scientific
question?
•
•
•
It is certainly a question that impinges
upon science. Our answer to the question
has profound implications for the shape
of evolutionary biology.
We can evaluate competing scientific
programs that take different positions.
But, in the end, it is also a philosophical,
meta-scientific issue.
Objection: ID involves an appeal to
miracle, the inscrutable
• “God did it” is no explanation. True.
• But neither is “Chance did it”. At this level of
generality, the two answers are equally
vacuous.
• At this point, Darwinists have no specific,
testable scenarios to offer us, detailing how
chance modification at the genetic level
produced any of the intricate functions we find in
living things. This is true even of simple cases
like Finch beaks.
Objections: Darwinism explains the
Appearance of Design
•
•
Things in the world, especially living things, look
as though they have been designed. Nothing
that we know looks designed unless it is
designed. Therefore there must have been a
designer, and we call him God.
Thanks to Darwin, it is no longer true that
nothing that we know looks designed unless it is
designed. Evolution by natural selection
produces an excellent simulacrum of design,
mounting prodigious heights of complexity and
elegance. Richard Dawkins, The God Delusion,
p. 79
Evidence of Evolution
Evolution also posits that modern organisms should show a
variety of structures from simple to complex, reflecting an
evolutionary history rather than an instantaneous creation. The
human eye, for example, is the result of a long and complex
pathway that goes back hundreds of millions of years. Initially
a simple eyespot with a handful of light-sensitive cells that
provided information to the organism about an important
source of the light; it developed into a recessed eyespot...
[which] provided additional data on the direction of light;... then
into a pinhole camera eye that is able to focus an image on the
back of a deeply-recessed layer...,; then into a pinhole lens
eye that is able to focus the image; then into a complex eye
found in such modern mammals as humans. Michael Shermer,
Why Darwin Matters: The Case Against Intelligent Design
(2006), p. 17.
Bad Design?
The anatomy of the human eye, in fact, shows anything but
“intelligence” in its design. It is built upside down and
backwards, requiring photons of light to travel through...
blood vessels, ganglion cells, amacrine cells, horizontal
cells, and bipolar cells before they reach the light-sensitive
rods and cones that transduce the light signal into neural
impulses...
Ospreys have eyes we have calculated to be sixty times
more powerful and sophisticated than our own and...
blindness, often caused by microscopic parasites that are
themselves miracles of ingenuity, is one of the oldest and
most tragic disorders known to man. Christopher Hitchens,
god is not Great, Twelve, NY, 2007, pp. 82-3
Can God use Evolution?
•
•
Those who have yielded, not without a struggle,
to the overwhelming evidence of evolution are
now trying to award themselves a medal for their
own acceptance of defeat. The very magnificence
and variety of the process, they now wish to say,
argues for a directing and originating mind. In this
way they choose to make a fumbling fool of their
pretended god, and make him out to be a tinkerer,
an approximator, and a blunderer, who took
aeons of time to fashion a few serviceable figures
and heaped up a junkyard of scrap and failure
meanwhile.
Christopher Hitchens, god is not Great, 2007, p.
85
Can’t Detect Design on Empirical
Grounds
...such order is found all over the place where we have
as yet no reason to suppose that there is a designer.
Paley argued that if we found a watch on the ground
we should infer that it had been made by an intelligent
being. This is true, because we hardly ever find
watches except where the supposition of human
manufacture is antecedently plausible -- on people's
wrists, in their pockets, in jeweller's shops, and so on.
But if watches were found as commonly on the
seashore as shellfish, or as commonly on dry ground
as insects, this argument would be undermined. J. L.
Mackie, The Miracle of Theism, 1982, p. 144.
Detecting Design?
We would recognize ruins on another planet only insofar
as those ruins resembled, at least to some extent, the
methods of man. And our ability to recognize man-made
characteristics depends on our ability to identify
characteristics that are not found in nature.... We see,
therefore that the characteristics of design stand in
contradistinction to the characteristics of natural objects...
Now consider the idea that nature itself is the product of
design. How could this be demonstrated? Nature, as we
have seen, provides the basis of comparison by which we
distinguish between designed objects and natural objects.
George H. Smith, Atheism: The Case Against God
(Prometheus, 1989), pp. 267-8
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