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)

 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 the scientific method

THEORY hypothesis predictionsobservations tests consistent not consistent? modify hypothesis

What is the “Scientific Method”? AAdvantage of the scientific method. Results are unprejudiced. Results are repeatable. WWhich means that. Conclusions are testable.

 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”? F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 A mere Guess Unproved Lacks credibility “Just a Theory” Layman’s Terms

Scientific Law: AA statement of fact supported by evidence. EExplains an action or set of actions. AAccepted to be true and universal. CCan be a single mathematical equation.

S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 S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.

 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 SSome scientific theories. The theory of evolution. The theory of relativity. Quantum theory. T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 7 th  Wilson, J (2005) “Scientific Laws, Hypotheses & Theories”, wilstar.com/theories.htm, viewed Oct 7 th