Science and Pseudoscience Sorting Fact from Fiction J. David O’Dell, Ph.D.

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Science and Pseudoscience
Sorting Fact from Fiction
J. David O’Dell, Ph.D.
Associate Professor of Chemistry
Glenville State College
What is Science?
• From Latin scientia, meaning knowledge
• Often regarded as a knowledge base
• More specifically, scientific knowledge is
– Achieved by a systematic process
• Planned, ordered, methodical
– Involves observation and experimentation
– Is testable
– If a statement is incorrect, it must be able to be
proved incorrect
What is Science?
“Science is built up with facts, as a house is with
stones. But a collection of facts is no more a
science than a heap of stones is a house.”
Henri Poincaré (1854-1912)
French Mathematician, Theoretical Physicist, and
Philosopher of Science
What Isn’t Science?
• Topics that are outside the realm of science
– Matters of opinion
– Matters of faith
– Ethics/Morals
– Newly evolving theoretical fields
• Often outside scientific realm until technology develops
for testing
• Pseudosciences
– Presented as being scientific but are not
Scientific Method
•
•
•
•
•
•
•
Observations
Question
Hypothesis
Prediction
Experiment
Analysis
Peer Review
Peer Review Process
• Science is self correcting
– Many studies with flawed methodologies and
invalid conclusions are never published
– Some are published, then retracted when new
information becomes available
– In order for results to gain credibility, the results
must be repeated in subsequent experiments
Skepticism
• Skeptic
– One who only accepts information that is well
supported by evidence
• Denialist
– One who rejects information that is well
supported by evidence
• Evidence
– Assessed by accuracy of predictions
– Not eyewitness evidence, as in court
Terminology
• Law
– A descriptive statement (very often mathematical)
that applies to a very broad range of conditions
– Does not offer explanation
• Theory
– A highly accepted explanation of a phenomenon
– Repeatedly confirmed through experimentation
– Not in any way, shape, or form a guess or hunch
Facts, Theories, and Laws
• Fact
– An object, when dropped, will fall toward the center
of the Earth
• Law
– The force acting on the objects is directly proportional
to the product of the objects’ masses and inversely
proportional to the square of the distance between
their centers of mass.
• Theory
– Spacetime is curved by the mass of the Earth
Unscientific (Popular) Method
• Observation  Conclusion
• Post hoc, ergo propter hoc
– After this, therefore because of this
– Leads to erroneous conclusions
• Cold weather causes colds
• Good luck charm causes success
– Makes sense
• Joe got sick after eating that plant, so I’m not going to
eat that plant.
What’s Wrong with That?
• Lack of control group
– No way to know if the effect was the result of the
observed event or some other factor
• Lack of statistical analysis
– No way to know if observed differences are the
result of the treatment or just due to chance
Science
Self Correcting, but Sometimes Slowly
• Antivax movement
– Andrew Wakefield study (1998) linking autism to MMR
vaccine
– Small sample size
– Published in The Lancet
– Later retracted by the journal’s editorial staff (2010)
– Initially thought to be bad science, later discovered to be
fraud
• Perfect (albeit bad) example of post hoc reasoning
– Autistic children often begin to show symptoms around
the age of vaccination
Public Attitudes Toward Vaccines
• Persistence of misconceptions
– 2008 Survey
• 19% agree that vaccines linked to autism
• 43% not sure
– 2009 Survey
• 25% of parents believe vaccines cause autism
• 12% refused at least one vaccine
• Occurrence of childhood diseases now rising
Persistence of Misconceptions
• Antivax campaigns by celebrities
– Jenny McCarthy, Oprah Winfrey
• Comments by politicians
– “I will tell you that I had a mother last night come up to me
here in Tampa, Fla., after the debate. She told me that her
little daughter took that vaccine, that injection, and she
suffered from mental retardation thereafter.”
• Michelle Bachmann (R, Minnesota) 2012
– “It’s indisputable that (autism) is on the rise amongst
children, the question is what’s causing it. And we go back
and forth and there’s strong evidence that indicates that
it’s got to do with a preservative in vaccines.”
• John McCain (R, Arizona) 2008
Congressional Hearing
on Vaccines and Autism
• “I’m convinced that the mercury in
vaccinations is a contributing factor to
neurological diseases such as autism.”
• "It wasn’t so bad when a child gets one or two
or three vaccines… Mercury accumulates in
the brain until it has to be chelated.”
– Congressman Dan Burton (R, Indiana) 2012
Science Understanding Among
American Adults
• Science and Engineering Indicators 2012
– Knowledge of Scientific Facts
– Understanding of Scientific Process
– Belief in Pseudosciences
Scientific Facts
• The center of the Earth is very hot. (True)
• All radioactivity is man-made. (False)
• It is the father’s gene that decides whether the baby is a boy or girl.
(True)
• Lasers work by focusing sound waves. (False)
• Electrons are smaller than atoms. (False)
• Antibiotics kill viruses as well as bacteria. (False)
• The continents on which we live have been moving their locations
for millions of years and will continue to move in the future. (True)
• Does the Earth go around the Sun, or does the Sun go around the
Earth? (Earth around Sun)
• How long does it take for the Earth to go around the Sun? (1 year)
– Asked only if previous question answered correctly
Science Facts
9.00
Correct Responses
8.00
7.00
6.00
5.00
4.00
3.00
2.00
1.00
0.00
1992
1995
1997
1999
2001
Year
2006
2008
2010
Science Reasoning
• Two scientists want to know if a certain drug is
effective against high blood pressure.
• The first scientist wants to give the drug to 1,000
people with high blood pressure and see how many of
them experience lower blood pressure levels.
• The second scientist wants to give the drug to 500
people with high blood pressure and not give the drug
to another 500 people with high blood pressure, and
see how many in both groups experience lower blood
pressure levels.
• Which is the better way to test this drug?
Which One?
• First experiment has no control group
– Any observed change could not be legitimately
attributed to the treatment
• Second experiment has a control group
– Patients in the experimental group can be
compared to patients in the control group
• Second experiment is better than first
• Second experiment could be better
Percent Answered Correctly
Science Reasoning
100
90
80
70
60
50
40
30
20
10
0
1995
1997
1999
2001
2004
Year
2006
2008
2010
Actual Clinical Trials
• Randomized
– Test subjects have equal likelihood of being in the control group or the
experimental group
• Controlled
– Control group is as identical as possible to the experimental group
– Subjects in the control group take placebo
• Placebo should be undistinguishable from drug
• Double-blind
– Neither the test subjects nor the researchers know who is in which
group
• Replicated
– Sample size is sufficient to separate effects due to the treatment from
effects due to chance
Attitude Toward Pseudosciences
• Survey Question on Astrology
– Is it very scientific, somewhat scientific, or not at
all scientific?
• Astrology is not at all scientific
– If planets/stars/moons/asteroids have effect on
us, we could measure that effect
– Believing that horoscope was accurate does not
equate to evidence
• Confirmation bias
Survey Results
Astrology Not at All Scientific
Percent Answering Correctly
70
60
50
40
30
20
10
0
1979 1983 1985 1988 1990 1992 1995 1997 1999 2001 2004 2006 2008 2010
Year
Pseudoscience
• Ideas which are presented as being scientific,
but which fail to meet the standards of being
scientific
Pseudoscientific Method
•
•
•
•
•
Conclusion
Experiment (sometimes)
Accept data that support conclusion
Reject data that contradict conclusion
Never modify conclusion
Dowsing
• Locating water, minerals, other substances by
use of divining rods
– No scientific reason the process should work
– No controlled scientific study has ever shown it to
work
– Another example of post hoc reasoning
• The dowser said there would be water here, and we got
a good well
– How does the dowsing rod know what the dowser
is looking for?
Why Does it Appear to Work?
• Ideomotor Effect
– Psychological phenomenon
– Unconscious response
– Phenomenon behind operation of Ouija board
• Device will point to where the operator knows
or thinks the target is
Scientific Evaluation
• Munich Experiment 1987-1988
– 500 dowsers tested for their “skill”
– Best 43 were selected for further study
– Subjects were asked to identify location of water
running through pipe
– Hundreds of tests during two-year period
– Six dowsers found to have results better than chance
– Independent data analysis concluded that
unconventional statistics used to show the six better
than chance
What’s the Harm
• ADE 651 bomb detector
– Dowsing devise used by Iraqi police to detect bombs
– Claims to detect guns, bombs, ammunition, bodies
• Global Technical GT 200 bomb detector
– Used in Thailand, Mexico
• Sniffex bomb detector
– Purchased by U.S. military for testing
• All have been shown to be no better than chance
at detecting anything.
Intelligent Design
• Actually creationism
– “Designer” substitutes for God
– “Design” substitutes for creation
• Creationism not pseudoscience, but rather is outside
the realm of scientific study
– Not testable
– Based on faith rather than observation and
experimentation
• Intelligent design is pseudoscience because it presents
religion as being scientific
– Used in attempt to get creationism taught in science
classes of public schools
Kitzmiller v. Dover Area School District
• 2004, Dover, Pennsylvania
• School board required teaching of intelligent
design as alternative to evolution
• Tried in U.S. District Court for the Middle
District of Pennsylvania
– Judge John E. Jones III
– Conservative Republican appointed 2002 by
George W. Bush
Basis For Lawsuit
• Intelligent design is not scientific, but is
religious
• Teaching intelligent design violates the
Establishment Clause of the First Amendment
– “Congress shall make no law respecting an
establishment of religion, or prohibiting the free
exercise thereof . . . .”
Decision of the Court
• “For the reasons that follow, we conclude that
the religious nature of ID would be readily
apparent to an objective observer, adult or
child.”
• “The evidence at trial demonstrates that ID is
nothing less than the progeny of creationism.”
• “. . . we find that while ID arguments may be
true, a proposition on which the Court takes
no position, ID is not science.”
Decision of the Court
• “. . . it is additionally important to note that ID
has failed to gain acceptance in the scientific
community, it has not generated peer-reviewed
publications, nor has it been the subject of
testing and research.”
• Accordingly, we find that the secular purposes
claimed by the Board amount to a pretext for the
Board’s real purpose, which was to promote
religion in the public school classroom, in
violation of the Establishment Clause.
Decision of the Court
• “The citizens of the Dover area were poorly
served by the members of the Board who
voted for the ID Policy. It is ironic that several
of these individuals, who so staunchly and
proudly touted their religious convictions in
public, would time and again lie to cover their
tracks and disguise the real purpose behind
the ID Policy.”
Decision of the Court
“Those who disagree with our holding will likely mark it
as the product of an activist judge. If so, they will have
erred as this is manifestly not an activist Court. Rather,
this case came to us as the result of the activism of an illinformed faction on a school board, aided by a national
public interest law firm eager to find a constitutional test
case on ID, who in combination drove the Board to adopt
an imprudent and ultimately unconstitutional policy. The
breathtaking inanity of the Board’s decision is evident
when considered against the factual backdrop which has
now been fully revealed through this trial.”
What’s the Harm?
• Gives students wrong idea about “controversy”
– There is no scientific controversy regarding evolution,
the age of the earth, the age of the universe, or other
“controversial” topics
• Gives students a disadvantage when studying
science
– Attempts to stifle critical thinking
• Give students the false impression that science
and religion are mutually exclusive
Homeopathy
• Samuel Hahnemann’s “law of similars” (1796)
– Like cures like
– If a concentrated solution causes symptoms, then
a dilute solution alleviates symptoms
• More dilute solutions are more potent
• Dilutions are typically so large that no
molecules of the original substance remain
• Implies that water has a “memory” for the
active ingredient
Developing Homeopathic Remedies
• “Proving”
– Administer substance to healthy individuals
– Record all symptoms which occur after ingestion
• “Succession”
– Extract material in water or ethanol
– Grind solids with lactose
– Perform several serial dilutions
Serial Dilutions
• Centesimal Scale
– Substance diluted by factor of 100 at each stage
• Hahnemann advocated 30C dilutions
– Substance diluted by factor of 100, then that
solution is diluted by a factor of 100, until the
serial dilution has been performed 30 times
– Results in a solution that has been diluted by a
factor of 10030 or 1060.
– Equivalent to putting much less than a drop of the
substance in Earths oceans
Dilution Terminology
• 4C = a 100-fold dilution performed four times
– Dilution factor of 1004 or 108
– Approximately equal to putting one drop of active
ingredient in 1300 gallons of water
• 6X = a 10-fold dilution performed six times
– Dilution factor of 106
Active Ingredient
Anas barbariae hepatis et cordis extractum 200C
Inactive Ingredients
•Sucrose
•Lactose
Oscillococcinum
• French physician Joseph Roy examined flu
victims during 1917 Spanish Flu epidemic
• Claimed to find oscillating bacterium in blood
of flu victims; named the bacterium
Oscillococcus
• Searched animals for the bacterium, claimed
to find the bacterium in a duck liver
200C Dilution
• Diluted by a factor of 100200, or 10400
• Equivalent to diluting one drop of substance in
a sphere the size of the solar system
• And then repeating the dilution process eight
times!
Other Ailments
• Nausea?
– Try ipecacuanha.
• Can’t sleep?
– Try coffea.
Why Do Pseudosciences Persist?
• “It’s easier to fool people than to convince
them that they have been fooled.”
– Mark Twain
• Publicity in the media
– Finding Bigfoot (Animal Planet)
– Ancient Aliens (History International)
– Ghost Hunters (Syfy)
– Long Island Medium (TLC)
– The Dr. Oz Show (syndicated)
Conclusions
• Science provides method for systematically
studying the physical world and gaining a greater
understanding of its processes.
– These processes are not affected by our beliefs, our
feelings, or our opinions of them.
• There are many topics which are outside the
realm of science.
– These topics cannot be studied by the scientific
process.
– Science and these topics are not mutually exclusive.
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