Science & pseudoscience – Part of chapter 3 popular (but incorrect) culture

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Science & pseudoscience –
Part of chapter 3
Including guest appearance by religion &
popular (but incorrect) culture
Goals & Outcomes
• Appreciating science in general, and astronomy in
specific.
• Distinguishing scientific from non-scientific work,
and therefore understanding what science is.
• Developing a working knowledge of the scientific
method and how to apply it to real world situations.
• Judge whether a particular study is a science or a
“pseudo-science” using the scientific method.
Learning Objectives
• Understand the Scientific method
– Limitations to pure objectivity
– Compare to non-scientific analysis & religion
• Understand the definitions of the word “theory”
as used by scientists compared to non-scientists
• Understand what kinds of questions can and
cannot be addressed by science
• Know some of the “tricks” of pseudoscience that
make it so believable.
Scientific Method
Cyclical process – can (re-)start anywhere in the cycle.
1.
6.
Make observations Ask a question
If hypothesis fails: Revise
or reject the hypothesis
If hypothesis didn’t fail:
Look for new predictionsReal world
Real biases
5. Share
results/ ideas
with others
(not in book)
Science is useless if
nobody learns!
2. Form hypothesis
= model of nature
3. Make a prediction about
something new
Personalities
(Objectivity p. 83)
4. TEST IT - Careful observations taken to
determine if observations disprove the
hypothesis. Try to isolate the cause/effect -- Control groups,
examine only one thing at a time, remove psychological effects.
Which step is most difficult for
astronomers compared to other
scientists?
1.
2.
3.
4.
5.
6.
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Asking question
Forming hypothesis
Making prediction
Test hypothesis
Share ideas/results with others
Revising/rejecting hypothesis
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Calif. Elementary School Science
Standards for scientific inquiry
•
From California Science Standards, taken from
throughout the K-12 standards
–
What is science?
•
Scientific progress is made by asking meaningful questions
and conducting careful investigations.
– Distinguish between hypothesis and theory as scientific terms.
– Recognize the usefulness and limitations of models and theories as
scientific representations of reality.
–
Ask question
•
Develop a testable question.
Calif. Elementary School Science
Standards for scientific inquiry
•
From California Science Standards, taken from
throughout the K-12 standards
–
Predictions:
•
•
•
Make predictions based on observed patterns and not random
guessing.
Predict the outcome of a simple investigation and compare
the result with the prediction.
Formulate and justify predictions based on cause-and-effect
relationships
Calif. Elementary School Science
Standards for scientific inquiry
•
From California Science Standards, taken from
throughout the K-12 standards
–
Testing hypotheses:
•
•
•
•
•
•
Collect data in an investigation and analyze those data to develop a logical
conclusion.
Repeat observations to improve accuracy and know that the results of
similar scientific investigations seldom turn out exactly the same because
of differences in the things being investigated, methods being used, or
uncertainty in the observation.
Conduct multiple trials to test a prediction and draw conclusions about the
relationships between predictions and results.
Differentiate evidence from opinion and know that scientists do not rely
on claims or conclusions unless they are backed by observations that can
be confirmed.
Evaluate the accuracy and reproducibility of data.
Identify and communicate sources of unavoidable experimental error.
Calif. Elementary School Science
Standards for scientific inquiry
•
From California Science Standards, taken from
throughout the K-12 standards
–
Communication:
•
•
•
•
•
Communicate observations orally and through drawings.
Draw pictures that portray some features of the thing being
described.
Record observations and data with pictures, numbers, or
written statements.
Record observations on a bar graph.
Communicate the steps and results from an investigation in
written reports and oral presentations.
Identify and communicate sources of unavoidable
experimental error.
Calif. Elementary School Science
Standards for scientific inquiry
•
From California Science Standards, taken from
throughout the K-12 standards
–
Revising scientific models:
•
•
•
•
•
Formulate explanations by using logic and evidence.
Recognize whether evidence is consistent with a proposed explanation.
Make new observations when discrepancies exist between two
descriptions of the same object or phenomenon.
Identify possible reasons for inconsistent results, such as sources of error
or uncontrolled conditions.
Know that when an observation does not agree with an accepted scientific
theory, the observation is sometimes mistaken or fraudulent (e.g., the
Piltdown Man fossil or unidentified flying objects) and that the theory is
sometimes wrong (e.g., the Ptolemaic model of the movement of the Sun,
Moon, and planets).
Calif. Elementary School Science
Standards for scientific inquiry
•
From California Science Standards, taken from
throughout the K-12 standards
–
Human influences:
•
•
•
Differentiate observation from inference (interpretation) and
know scientists’ explanations come partly from what they
observe and partly from how they interpret their observations.
Know that when an observation does not agree with an
accepted scientific theory, the observation is sometimes
mistaken or fraudulent (e.g., the Piltdown Man fossil or
unidentified flying objects) and that the theory is sometimes
wrong (e.g., the Ptolemaic model of the movement of the
Sun, Moon, and planets).
Differentiate evidence from opinion and know that scientists
do not rely on claims or conclusions unless they are backed
by observations that can be confirmed.
Hallmarks of Science – figure 3.26 p 79
(Good scientific theories / good science)
There are 3 big ideas about “science” vs. other kinds of thinking.
1.
Have TESTABLE predictions (green circle in fig. 3.26)
TESTABLE means you must be able to prove the idea WRONG
2.
Seek NATURAL explanations of observations (blue circle fig 3.26)
Why natural? Those can be disproved! (blue circle)
These first two usually split science and religion.
3.
Pick the simplest model that explains observations. (Occam’s razor)
Make sure experiment is repeatable (pages 79 & 82).
Good science doesn’t need to be CORRECT. Very few good scientific
ideas ARE right, they often need modifications. Examples:
•
quantum physics, theory of relativity, “law of gravity.”
What’s in a name? Theories pp. 83-84
Everyday English uses “guess,” “theory,” and “hypothesis” as
synonyms.
Scientists do not.
Guess – any old random idea to explain observations
Hypothesis – an idea that can be tested
Theory – a hypothesis that has been tested a LOT and has
passed them all.
It can be wrong, but according to current research, that isn’t
likely.
Usually only needs minor modifications, if any.
A scientific Theory, like evolution, is NOT just a guess.
Evolution is the only good model that is backed by tests, data,
and evidence. It is the only scientific model of life.
California Elementary School
Science Standards for evolution
•
From California Science Standards, grade 7
–
Biological evolution accounts for
the diversity of species developed
through gradual processes over
many generations.
Religion vs. Science
No scientist claims a theory is definitely correct/perfect.
Theories can always be disproven later. (Gravity.)
All scientific matters can be tested. Not all religious ideas can be tested.
Science does NOT contradict religion
Science:
• how processes appear to be related.
• rules that nature follows
• NOT
why these rules work.
Science is testable
It’s religion if you can’t do an experiment to prove it wrong. Faith
Religion isn’t always testable. That doesn’t mean it’s wrong!
(Pseudo) Anti-Science p. 83
pseudo = false
Common and popular examples:
•Creationism ---------------- Religion with science words
(Intelligent design)
•Astrology
(NOT science; don’t teach it in science class)
---------------- Predicting future by birth date
Fortune
20 million people = same birthday; 4 births per sec.
Tellers /
10,000 babies born in US every day.
(1 per 8 seconds)
Psychics
•Palm reading, Tarot cards - Semi-legit! Acting mixed with
spoken & body language
interpretations! Personality reading!
Astrology, Palm Reading, etc. tend to make very general predictions which YOU then
match to observations of your life. Or they ask leading questions, and they follow your
lead.
I’m on a soapbox for this slide…
Anti-Science in popular American culture
• No scientific study has linked vaccines to having autism.
–
There used to be one science study, but it was recently disproven
–
–
–
–
Many scientific studies link lack-of-vaccines to getting sick.
In first half of 2008, measles more than tripled in the USA.
Most cases were kids who didn’t get a vaccine, fearing autism.
Measles can kill you. It is contagious.
–VACCINES SAVE LIVES!
– See http://www.sciencebasedmedicine.org/?p=384
• Almost all (90+%) science indicates global warming is
human-caused and will cause environmental and financial
damage over the next 100 years.
– My generation can’t / won’t fix the problem.
– Your generation will have to.
By definition, a scientific theory can
also be a fact
1. True
2. False
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Summary
Science
Testable
No conflict with religion
How can we test that? How can we know?
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