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Limitations of Science
Physical Science 410
James Mackey
Having some understanding of the
Characteristics of Science, it is now
important to recognize that science
while a truly magnificent activity still
has its limitations
We will discuss the Limitations of Science
in the following areas:
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Science is…
1. Human Enterprise
2. NOT the ONLY Way to Knowledge
3. Based on Repeatable Events
4. Cannot Deal with Teleological Questions
5. Pragmatic
6. Incomplete
7. Partially Relative
• 8. Statistical
1. Human Enterprise - Based on
Natural Categories
• The human viewpoint can never be
completely removed from science
• All science is built upon human
presuppositions that are always made but almost never stated
“There are no bare uninterpreted
data in science. Expectations
influence perceptions, both in
everyday life and in science....…
The process of measurement, and
the very language in which the
results are reported, are influenced
by prior theories.........
Ian Barbour, the Winifred and Atherton Bean Professor Emeritus of Science,
Technology and Society at Carleton College, won the 1999 Templeton Prize for
Progress in Religion. A physicist and theologian, Barbour is credited with
launching a new era in the interdisciplinary dialogue between science and religion
and is one of the world's most forceful advocates for ethics in technology. He has
written at least 6 books on Science and Religion, including Issues in Science and
Religion(1966), credited with creating the field of science and religion studies
....The predicates we use in describing
the world, and the categories with which
we classify events, depend upon the kind
of regularities we anticipate. The
presuppositions the scientist brings to his
inquiry influences the way he formulates
a problem, the kind of apparatus he
builds, and the type of concept he
considers promising.”
Barbour
A quotation from Giancoli’s The Ideas of
Physics makes this viewpoint very clear
“Science is a human endeavor. The practice
of science is built on the unprovable
assumption that a real physical world exists
independently of man. The existence of a
real physical world is taken for granted by
most scientists, artists, and for that matter
most everyone else.........
....Yet for centuries philosophers have
debated whether the physical world actually
exists or if it is only an illusion of our minds.
But why should we doubt the existence of a
world we can see with our own eyes? The
20th century philosopher-scientist Arthur
Eddington put it simply when he said, ‘the
mind is the first and most direct thing in our
experience, and all else is remote inference.’”
Continuing on, Giancoli later writes:
The simple view that scientists painstakingly
work through the steps of the ‘scientific
method’ is a fiction. So is the view that
scientists deal only with ‘facts’, facts that are
just waiting to be discovered with the
implication that these facts are absolute and
are not subject to interpretation or
judgement. Science builds not on facts but
on observations. And these observations are
open to interpretation and do require
judgement.”
Giancoli
How do presuppositions influence our science?
Assume:
All explanations must be naturalistic
p1
Humanity exists
p2
We got here somehow...
concl.
The explanation of our origin must
be naturalistic
Is this a valid argument?
YES
Another example is the conclusion drawn by
Carl Sagan in the popular book Cosmos:
the physical universe is...”all there is or ever
was or ever will be.”
Which is true IF one accepts Sagan’s
unstated presupposition that only the natural
world exists.
While good science strives to minimize the
number of preconceptions, real science cannot
exist without them
If you had no preconceptions at all......
what problem would you attack
what would you measure
how would you measure it
how would you gauge ‘good’ data
“Pure objectivity in real science is a
myth....it is the aim of science to
eliminate intrusion of this subjective
element, but it is also true that this
subjective element must constantly
be reckoned with.....
....Observations and measurements in
science are made by men. Scientific
theories are constructed by men.
Experimental programs are designed by
men. Data are interpreted by men. All of
these activities are done by individuals with
a particular cultural, academic, and scientific
orientation”
Richard H Bube, emeritus professor of Materials Science and former chair at
Stanford University. Former President of ASA and editor of JASA. Author of 6
books incl. The Human Quest (1971)
There is a faith component in science, these
usually, unstated presuppositions that are
assumed to be true....
Some obvious examples are:
the laws of physics are the same everywhere
the laws of physics are the same everywhen
nature is rational
nature is comprehensible
Albert Einstein once wrote..
“The most incomprehensible thing about
the Universe is that it is
comprehensible!”
Physicist Alan Goodman, who lectures for the
Union of Concerned Scientists, observed that..
“It was faith in the dependability of the laws
of conservation - that space is homogeneous
and isotropic, and that time is homogeneous
- that lead Wolfgang Pauli in 1930 to predict
the existence of neutrinos, for example,
though we couldn’t observe them until 1953.”
Yoeman
A wonderful quote from Cryogenic Physicist
Leon Cooper
(1930) is an American physicist and Nobel Prize laureate (1972), who with
John Bardeen and John Robert Schrieffer, developed the BCS theory of
superconductivity. He is Thomas J. Watson, Sr. Professor of Science at
Brown University, and Director of the Institute for Brain and Neural
Systems.
“The foremost supposition is the belief that
the world outside ourselves, outside our own
minds, exists. This belief is so primitive that it
is very likely shared by all, except animals
lowest on the evolutionary scale and some
philosophers (whose position on the
evolutionary scale I cannot guess)”
continuing on, he writes....
“But this belief (the universe is ordered) -
daring, naive, and, considering the almost
endless variety of our experience, not at all
obvious - that order can be found, has moved
scientists from Thales to Kepler to authors in
the latest issues of Physical Review Letters to
create science. For what we call modern
science is as much an attitude of mind - a
belief in the possibility of a certain kind of
understanding - as a set of principles or
methods”
Cooper
Based on this we might ask…
Why should this be so that
“the universe is ordered”
Recall that Einstein wrote “The most
incomprehensible thing about the Universe is
that it is comprehensible!”
Is this really incomprehensible?
A rational God making an appropriate place for
his creations to live & exercise their intelligence
“Another aspect of physics, not yet
mentioned, is a fundamental article of faith.
In general physicists believe that there
are fundamental principles governing nature.
The universe seems to be law-abiding
and not capricious.
In broad patterns, there seems to be
regularity and order. Even the small scale
disorder and unpredictability associated with
atomic scale objects seems to be defined
within comprehensible limits........
...The physicist counts on nature to ‘play
fair’, and not change the rules in the middle
of the game. The fun of the game, the
intrigue of the plot, the excitement of the
chase arise from the realization that, given
any particular set of ‘facts’ or objective
observations, there are many possible
hypotheses or theories which can be framed
to accommodate them.
Further testing must be done to
determine which of several alternate
theories is most acceptable in terms of
simplicity, agreement with what is known
(or perceived), what is suggested by way
of further theory or experiments, and (it
must be admitted) a subjective
judgement of the ‘niceness’ of the
theory.”
“...Once a theory is well established, and
widely accepted, it is difficult to disturb it.
If a new experiment brings up evidence
contrary to the theory, most scientists will
challenge the validity of the evidence
rather than abandon the theory - only the
most persistent and persuasive evidence
results in significant modifications of
established theory.”
Read
2. Science is not the Only Way to
Knowledge
• Knowledge can be acquired at least 3
ways
– scientific knowledge
– experiential knowledge
– revealed knowledge
The philosophy of Scientism holds that only
scientifically obtained knowledge is meaningful
(recall the quotation from the philosopher
Mehlberg)
Such an idea denies the possibility of any
real knowledge being presented or
discovered in any human art - which would
deny the relevance of the philosophy of
scientism since philosophy is not a scientific
activity
Refer back to Bube’s statement about science
as a way of knowing based on sensory data
Roger John Williams (1893 – 1988), was an American
biochemist who named folic acid and discovered pantothenic
acid, a member of the National Academy of Sciences and
President of the American Chemical Society.
Pictured here in 1974 with Nobel Laureate Linus Pauling (on
left)
In a wonderful little book called You Are
Extraordinary, biochemist Roger Williams writes
“In attempting to do this (examine the facets
of God), we use our minds the same as when
we think of anything else. Some regard
religious thinking and faith as belonging in a
separate compartment from scientific
thinking…….
…but I see no basic difference. In
science we make by intuition,
hypotheses and theories in which we
have some faith - sometimes too
much. In religious thinking we make
or consider hypotheses in which we
have some faith - also sometimes too
much. The difference is in the
subject matter of our thinking...
In science we make hypotheses and
theories about things that can be
verified by scientific experiment;…...
..in the religious realm our hypotheses
and theories concern matters where
experimentation, in the scientific sense,
may be impotent….”
Williams
Experiential knowledge
Clearly there are some things that a person may
know because of direct experience. While this is
generally subjective - it is none the less real:
individual consciousness
personality
Revealed knowledge
There are many things, esp. in the religious realm
that one could not know without some revealed
source.
While God’s general nature (divinity & power) can
be known by all, (Rom. 1), only through scripture
do we learn of his loving and caring nature, his
plan for restitution of man, and guidelines for living
in a fallen world.
3. Science is Based on Repeatable Events
• The strongest scientific knowledge and
understanding is based on events that can
be replicated at will by different observers
at different times
• Single-time events can only peripherally be
dealt with in a scientific sense
– all that can be required is that any
speculations be consistent with data that
can be reproduced
When single-time, non repeatable
events (i.e. creation of the
universe) is treated “scientifically”,
a careful scientist will be cautious
about the final conclusions being
drawn from whatever data exists
Watch for the differences between the ‘popular’ writings
of scientists and their ‘peer-reviewed articles’
“If an experiment reveals
unexpected and perhaps startling
results, the most important
questions asked of the
experimenter is; Are your results
repeatable?
Thus science is in a sense self-correcting,
for the scientist trusts only those ‘facts’
that are the same in different
laboratories for different observers, and
on different days of the week.”
Booth
Wed
4. Science cannot Answer Teleological
Questions
• Science deals with the interactions
between and the relationships among
natural phenomena and conseq. cannot
deal with any ‘final’ or ‘ultimate’ whys
“The last thing in the world that a scientist
can answer is a question about the ultimate
constitution of matter (except where he talks
as an ordinary man)….
…He may think he can; but this question
is beyond investigation. The scientist
cannot answer any questions about
existence. All questions about existence
- the modes of being,
- the grades of being,
- the essential distinctions among beings
lie outside the competence of the
scientist...
He cannot answer by his method,
the three great questions that
Kant said were the great
philosophical questions:
the immortality of the soul,
the freedom of the will, and
the existence of God….
…The scientist cannot answer any questions
about the nature of knowledge. What
knowledge is, is itself a question not open to
(scientific) investigation. It is not a scientific
question. These are all intelligible questions,
but science cannot answer them. Moreover,
my position here is not just that science
cannot answer them now, but that science
cannot answer them ever.”
Adler
“The goals of nature is an idea
foreign to science, and although
the scientists in unguarded
moments frequently enough uses
the word ‘cause,’ he will, if pressed,
say that he does not seek the
causes of effects but only
relationships among
phenomena…...
..Explanation in science is reduced to
relationships; one thing is ‘explained’ by
being related to something else.
“A good theory is not one that
gives an ultimate cause of
events, but merely one that
relates many different events
through a few simple ideas and
equations.”
Ford
“In our description of nature the purpose is
not to disclose the real essence of the
phenomena but only to track down, so far as
it is possible, relations between the manifold
aspects of our experience.”
Niels Bohr, “Atomic Theory and the Description of Nature: Four
essays with an Introductory Survey” Macmillan, NY (1934), p18
Niels Bohr (1885 – 1962) was a Danish physicist who made
fundamental contributions to understanding atomic structure and
quantum mechanics, for which he received the Nobel Prize in Physics
in 1922. Bohr mentored and collaborated with many of the top
physicists of the century at his institute in Copenhagen. He was part
of a team of physicists working on the Manhattan Project. One of his
sons, Aage Bohr, grew up to be an important physicist who in 1975
also received the Nobel prize. Bohr has been described as one of the
most influential physicists of the 20th century
5. Science is Pragmatic
• In science, whatever works and can be
independently verified is accepted as so!
• Absolute truths and Scientific truths are
different
– absolute truths are unchanging
– scientific truths are always evolving
According to Isaac Newton..
“…analysis consists in making
experiments and observations, and in
drawing general conclusions from them
by induction, and admitting no
objections against the conclusions, but
such as are taken from experiments or
other certain truths…..
...And although arguing from
experiments and observations
by induction be no
demonstration of general
conclusions, yet it is the best
way of arguing which the
nature of things admits of, ...
A good scientific description is one that
works, i.e. conforms to experiment, while a
bad scientific description is one that doesn’t
work, i.e. does not conform to experiment.
caution!
Since a pragmatically good description
conforms to experiment (by definition!), it is
often wrongly concluded that experimental
measurements (i.e. the way things seem to be)
prescribes how things ought to be.
6. Science is Incomplete
• A careful scientist does not claim a
complete and final description of anything.
• To do so would require knowing
everything about everything
• Dynamic nature of science illustrates the
flaw of viewing science as complete
“Science is inherently open-ended
and exploratory, and makes
mistakes every day. Indeed that will
always be its fate, according to the
bare-bones logic of Kurt Godel’s
Second Incompleteness Theorem.
Godel’s theorem establishes that the
full validity of any system, including
a scientific one, cannot be
demonstrated within that system
itself.
…In other words, the comprehensibility
of a theory cannot be established unless
there is something outside the frame
against which to test it - something
beyond the boundary defined by a
thermodynamics equation, or by the
collapse of the quantum wave function,
or by any other theory or law.
And if there is such a wider reference
frame, then the theory by definition does
not explain everything.
In short, there is not and
never will be a complete and
comprehensive scientific
account of the universe that
can be proven valid.”
Ferris
Ian Barbour, in Science and Secularity writes..
“The scientist is interested in regularities among
phenomena; he selects not according to the
importance of the problem, but according to its
tractability to his methods. Therefore he
cannot claim to give a complete account. Think
of Eddington’s (Sir Arthur Eddington, a famous
English scientist) parable about the Zoologist
studying deep sea life…..”
Ian Barbour, a Carleton College professor emeritus, received 1999 Templeton
Prize . Ian Barbour's Issues in Science and Religion, published in 1965, has been
credited with literally creating the contemporary field of science and religion.
This phenomena is known as a “selection effect”
Great care must be taken to avoid erroneous
conclusions based on such data.
“…if a rat catcher tells you that all
rats are no more than six inches
long because he has never caught
any that are shorter, you should
check the size of his traps before
drawing any far-reaching
conclusions about the length of rats.
Even though you are most likely to
see an elephant in a zoo, does not
mean that all elephants are in zoos,
or even that most elephants are in
zoos.”
Frank Tipler
John barrow
John Barrow & Frank Tipler, The Anthropic Cosmological
Principle, a great reference on design in the universe, once
you dismiss Barrow’s discussion of the WAP (weak anthropic
principle)
Any event usually has a complex series of
explanations on different levels of
understanding
Temporary Diversion
I LOVE YOU
This can be analyzed on a number of different levels
• 1. alphabet or letters
• 2. phonetics (interaction of letters give rise to
phonetic meanings)
• 3. individual words and their meanings (each word
has its own unique lists of possible meanings)
• 4. grammatically (the way in which the words
interact influences their meaning...e.g. You love I
• 5. context (the words I LOVE YOU on a ppt. slide is
vastly different than the words I LOVE YOU said to
another individual)
• 6. ultimate context (what is the ultimate meaning of
really loving some one)
Conclusion
• 1. a thing may be described on many levels
• 2. in principle, an exhaustive description is possible on
each level, especially lower ones
• 3. an exhaustive description on one level does not
influence the significance or necessity for an
exhaustive description on another level
• 4. a total or complete description of a topic would
require an exhaustive description on every level
7. Scientific Understanding is Partially
Relative
• Scientific understanding is always relative to
the existing world-view of practicing scientists
• Our perceptions of nature are strongly
influenced by our world view
• All science is based on units of measures and
standards that are determined solely by
consensus agreement - not absolute
standards
“There are no bare uninterpreted data in
science - Expectation influences perceptions,
both in everyday life and in science. The
process of measurement, and the very
language in which results are reported, are
influenced by prior theories….
…The predicates we use in describing the
world, and the categories with which we
classify events, depend on the kinds of
regularities we anticipate….
The presuppositions which the scientist
brings to his inquiry influence the way
he formulates a problem, the kind of
apparatus he builds, and the type of
concept he considers promising.”
Barbour
How would you begin to do an
experiment on something you
know absolutely nothing about?
The existing world-view of science may force
the rejection of ideas ultimately proven correct
1944 Oswald Avery discovers DNA was
the hereditary substance
1950 Symposium “Genetics in the 20th
Century” - only one negative reference
1914-16 Michael Polanyi and theory of
adsorption of gases on solids
Soundly rejected
Avery was one of the first
molecular biologists and a pioneer
in immunochemistry, but he is best
known for the experiment
(published in 1944 with his coworkers Colin MacLeod and Maclyn
McCarty) that isolated DNA as the
material of which genes and
chromosomes are made
Years later Polanyi wrote about this:
“This miscarriage of the scientific method could
not have been avoided…There must be at all
times a predominantly accepted scientific view of
the nature of things, in the light of which
research is jointly conducted by members of the
community of scientists. A strong presumption
that any evidence which contradicts this view is
invalid must prevail. Such evidence has to be
disregarded, even if it cannot be accounted for,
in the hope that it will eventually turn out false
or irrelevant.”
Polanyi
8. Science is Statistical
• All measurements, except counting (unless
one counts wrong) are approximate and
have errors
“Every regularity in nature, be it summarized in a
law, principle, or theory is discovered through
observations or is based on individual
observations that have some uncertainty
attached to them. Therefore every scientific
statement involves some uncertainty. Its
corollary is that nothing is absolutely certain in
science”
Barbour
“The competent scientist never speaks of
‘proving’ a theory but only of obtaining a
sufficient degree of confidence in it. He may
speak of a theory as being acceptable, valid or
invalid, but never of it being true or false. For
one thing, what is truth in the context used
here? Is truth absolute?..certainly it is not in
the scientific sense…In science there is no
such thing as absolute certainty; there is at
best only a high degree of probability.”
Barbour
Remember
• Science acts to try to falsify or disprove a
given model rather than try to prove a
model is true
Some parts of science are inherently probabilistic
Decay of a single atom...
Electron probability distribution function
Heisenberg Uncertainty Principle
“Physical laws rest on atomic statistics and are
therefore only approximate.”
Erwin Schroedinger
To see one way a christian mechanist deals with
this….
“The processes of the world seem to depend
for their fruitfulness upon an interplay between
chance and necessity. A random event (an
aggregation of atoms, a genetic mutation)
produces a new possibility which is then given
a perpetuating stability by the regularity of the
laws of nature. Without contingent chance,
new things would not happen. Without lawful
necessity to preserve them…they would soon
vanish away…..
….The universe is full of the clatter of
monkeys playing with typewriters, but
once they have hit on the first line of
Hamlet it seems that they are
marvelously constrained to continue to
the end of at least some sort of play.”
John Polkinghorne KBE FRS (born October 16, 1930,
in Weston-Super-Mare, England) is a British particle
physicist and theologian. He has written extensively
on matters concerning science and faith, and was
awarded the Templeton Prize in 2002. He was
instrumental in the discovery of the Quark
Notice the appeal to some “unknown” factor to explain
existence – rather than the possibility of intelligence …
A proper understanding of science in no way
indicates that belief in a creator is a reflection of
ignorance or wishful thinking, nor does it imply that
the believer already has the answer to everything
and therefore no reason to study.
To the contrary, science functions on
foundations that mechanistically have
absolutely no reason to exist
Many of the problems stem from scientific
ignorance of religion and religious ignorance of
science!
Do not contribute to
this problem!
Terminate!