Acquiring
Knowledge in
Science
Some Questions
 What is science and how does it
work?
 Create a list of words to describe
science
 Which ways of knowing are used in
science? Explain how each is used.
The Scientific Method
 “Science is best defined as a careful,
disciplined, logical search for
knowledge about any and all aspects of
the universe, obtained by examination
of the best available evidence and
always subject to correction and
improvement upon discovery of better
evidence. What's left is magic - and
magic doesn't work.”
(James Randi)
The Scientific Method
 A better approach than explaining
something as magic is to do
experiments and perform careful
observations.
 The results of this approach are
universal in the sense that they can
be reproduced by any skeptic.
 This is the fundamental basis of the
scientific method
What is the “Scientific
Method”?
 The scientific method is the best way
yet discovered for separating the truth
in nature.
 the scientific method
THEORY
consistent
observations
hypothesis
not
consistent?
modify
hypothesis
tests
predictions
What is the “Scientific
Method”?
 Advantage of the scientific method.
• Results are unprejudiced.
• Results are repeatable.
 Which means that.
• Conclusions are testable.
What is the “Scientific
Method”?
 The conclusions will hold irrespective
of the state of mind, or the
religious persuasion, or the state of
consciousness of the investigator
and/or the subject of the
investigation.
What is the “Scientific
Method”?
 Faith, defined as:“belief that does not rest on logical
proof or material evidence”,
does not determine whether a scientific
theory is adopted or discarded.
Links to language
 What does the word “theory” mean
to you?
Scientific Laws, Hypotheses,
and Theories
Layman’s
Terms
Lacks
credibility
“Just a
Theory”
A mere
Guess
Unproved
Scientific Law:
 A statement of fact supported by
evidence.
 Explains an action or set of actions.
 Accepted to be true and universal.
 Can be a single mathematical equation.
Scientific Law:
 Some scientific laws.
• Law of gravity,
• Law of thermodynamics,
• Hooke’s law of elasticity.
Isaac Newton’s Inspiration
Nothing yet,
how about
you Newton!
Hypothesis:
 Educated guess.
 Based upon observation.
 Rational explanation of a phenomenon.
 Not been proved.
 Supported / refuted by experimentation.
Johannes Kepler’s Uphill Battle
So you see, the
orbit of a planet is
elliptical
What’s
an orbit?
What’s a
planet?
What’s
elliptical
?
Theory:
 Explanation of a set of related
observations.
 Based upon proven hypotheses.
 Verified multiple times by detached
groups of researchers.
Scientific Laws, Hypotheses,
and Theories
 So, what’s the difference between a
“Law” and a “Theory”
• Both are accepted to be true by the
scientific community.
• Both are used to make predictions of
events.
• Both are used to advance technology.
Scientific Laws, Hypotheses,
and Theories
 A theory is much more complex and
dynamic
 A theory explains a whole series of
related phenomena.
 A law governs a single action.
 A law is accepted as true with little
research or study being done on it
 A theory is also accepted as true, but
research is being done to fine tune it
Scientific Laws, Hypotheses,
and Theories
 Some scientific theories.
• The theory of evolution.
• The theory of relativity.
• Quantum theory.
 These theories are well
documented and proved beyond
reasonable doubt.
The Role of Induction and
Falsification in Science
 Observation leads to recognition of a
pattern –we use induction to create a
hypothesis
 We test our hypothesis using
experimentation –we need to do this many
times in order to be fairly certain that our
hypothesis is true
The Role of Induction and
Falsification in Science
 But can we ever be certain that our hypothesis is
100% true? Even one false result can cause our
theory to be abandoned
 Karl Popper –Idea of Falsification
 A hypothesis is a statement that can be
(potentially) falsified
 If it is not falsifiable, then it is not science
The Role of Induction and
Falsification in Science
 Some people have criticized the idea of
Falsification
 For example, if we create a new organic
compound in chemistry, how does
falsification enter into this? If I invent an
new car engine, where does falsification fit
into this?
Scientific Claims
 A scientific claim is a claim that should
lend itself to experiment
 We should be able to devise an
experiment that could falsify the claim
 Try to distinguish scientific claims from
non-scientific claims on the sheet (pg 19
Alchin)
Scientific Truth
 It can never be proved experimentally
that a claim is correct, but it can be
proved that a claim is wrong –this is called
falsification
 No matter how good our theories are,
there is always the possibility that they
will be shown to be incomplete or wrong
 Science has an inductive component
Think about this:
 If science never proves anything
right, why do we trust it so much?
The Progression of Scientific
Knowledge
Scientific Detectives
 Get into groups of 3 or 4
 Your group will be given a deck of cards
 The object of this activity is to deduce the “rule” that Mr.
Thiessen uses to accept cards.
 One person from your group will present one card to Mr.
Thiessen –the card will be either accepted or rejected
 You will use the Scientific method and write down all
the steps taken to deduce the “law of acceptance”
Record the steps of the scientific
method
 (1) Observation –describe exactly when a card was
accepted and when a card was rejected –you should
observe several card attempts before making a …
 (2) Hypothesis –make a guess about the reason(s) for
acceptance and the reason(s) for rejection
 (3) Prediction -send many known cards to Mr. Thiessen
and predict the results (accept or reject)
 (4) Experiment –Observe the results of the sent cards
 (5) If you are ready, make a Conclusion
 Otherwise, revise your Hypothesis and go back to step (2)
Acknowledgements
 Harris, S (2005) “Johannes Kepler’s uphill battle”
 Larson, G (2005) “Newton’s Inspiration”
 Wudka, J (2005) “The Scientific Method”,
phyun5.ucr.edu/~wudka/Physics7/Notes_www/node6
.html,viewed on Oct 7th
 Wilson, J (2005) “Scientific Laws, Hypotheses &
Theories”, wilstar.com/theories.htm,
viewed Oct 7th