Nature of ScienceNature of Science

Woodrow Wilson Indiana Woodrow Wilson Indiana Teaching Fellowships Teaching Fellowships

Summer 2010Summer 2010

SCIENCE is…SCIENCE is…

the search the search for for relationships relationships that that explainexplain and and predictpredict the behavior the behavior of the of the universe.universe.

Science has also been described as Science has also been described as the process the process of model buildingof model building, in which models serve to , in which models serve to simplify observed phenomena and relationships.simplify observed phenomena and relationships.

See Gilbert & Boulter (2000)See Gilbert & Boulter (2000)

Scientific “models” may exist in several forms:Scientific “models” may exist in several forms:

Physical Physical (concrete; 3D objects)(concrete; 3D objects)GesturalGestural (kinesthetic; body movements) (kinesthetic; body movements)VerbalVerbal (spoken/written; analogy; metaphor) (spoken/written; analogy; metaphor)PictorialPictorial (visual diagrams; animations) (visual diagrams; animations)NumericalNumerical (data table; lists) (data table; lists)GraphicalGraphical (ordered pairs) (ordered pairs)MathematicalMathematical (equations; formulas) (equations; formulas)

Scientific HypothesisScientific Hypothesis

Most people agree that a scientific Most people agree that a scientific hypothesis can be defined simply as hypothesis can be defined simply as

an educated guessan educated guess..

We should, however, stress that it is We should, however, stress that it is educatededucated, meaning that there are , meaning that there are

plausible reasons for that decision.plausible reasons for that decision.

Scientific TheoryScientific TheoryThere is much misunderstanding about There is much misunderstanding about

what constitutes a what constitutes a scientific theoryscientific theory..

““In science, a theory is a mathematical or logical In science, a theory is a mathematical or logical explanationexplanation, or a , or a testable modeltestable model of the manner of the manner

of interaction of a set of natural phenomena, of interaction of a set of natural phenomena, capable of capable of predicting future occurrencespredicting future occurrences or or

observations of the same kind, and capable of observations of the same kind, and capable of being tested through experiment or otherwise being tested through experiment or otherwise

falsifiedfalsified through empirical observation. through empirical observation.”

Taken from Taken from http://en.wikipedia.org/wiki/Theory

Scientific LawScientific Law

A scientific law has been described as A scientific law has been described as a statement describing a natural eventa statement describing a natural event..

In many cases, scientific laws tend In many cases, scientific laws tend to to DESCRIBEDESCRIBE events, while scientific events, while scientific

theories tend to theories tend to EXPLAINEXPLAIN events. events.

It is It is NOT NOT a question of a question of TRUTHTRUTH..

The Scientific MethodThe Scientific MethodMany students of all ages are taught that “Many students of all ages are taught that “the the scientific methodscientific method” consists of steps such as:” consists of steps such as:

1)1) Make observationMake observation2)2) Formulate hypothesisFormulate hypothesis3)3) Test hypothesisTest hypothesis4)4) Evaluate hypothesisEvaluate hypothesis5)5) Change hypothesis and/or make more testsChange hypothesis and/or make more tests

It is important to note that scientific study It is important to note that scientific study involves involves a systemic process of a systemic process of

experimentation and evaluationexperimentation and evaluation, whether you , whether you begin with a hypothesis or with “trial and error.” begin with a hypothesis or with “trial and error.”

Joel A. Bryan, Ph.D.Joel A. Bryan, Ph.D.Department of Physics and AstronomyDepartment of Physics and Astronomy

Ball State UniversityBall State Universityjabryan@bsu.edujabryan@bsu.edu

It is the year 2347. The Earth’sIt is the year 2347. The Earth’s natural resources are exhausted.natural resources are exhausted. Scientists have determined thatScientists have determined that the Earth will most likely explodethe Earth will most likely explode in a very short time.in a very short time.

Bang!!!Bang!!!

The development of space travelThe development of space travel and other technological advancementsand other technological advancements have enabled scientists to prepare ahave enabled scientists to prepare a distant planet for human habitation.distant planet for human habitation.

You and a few others are fortunate toYou and a few others are fortunate to have been selected as representativehave been selected as representative members of planet Earth who willmembers of planet Earth who will survive and populate this new distantsurvive and populate this new distant planet.planet.

Upon arrival, you are relieved to findUpon arrival, you are relieved to find that the planet is indeed suitablythat the planet is indeed suitably prepared for human existence, justprepared for human existence, just as promised.as promised.

Your joy soon turns toYour joy soon turns to frantic dismay when youfrantic dismay when you discover that the solediscover that the sole member of your team withmember of your team with knowledge of the voice-knowledge of the voice- activated oxygen producingactivated oxygen producing machine has taken deathlymachine has taken deathly ill and no longer remembersill and no longer remembers the voice activation code.the voice activation code.

As your oxygen supply quickly depletes, As your oxygen supply quickly depletes, a close inspection of the voice-a close inspection of the voice- activated oxygen supply machineactivated oxygen supply machine reveals only a few vague instructions.reveals only a few vague instructions.

Oxygen

Speak here.

Instructions

“Oxygen is produced by spokennumerical code, of whichno number may be used

more than once.

Five consecutive invalid attemptswill cause this device tocompletely self-destruct.

Press here to begin, speakingloudly and clearly into the

microphone.”

Your task is to begin the processYour task is to begin the processof trying to determine the “code,”of trying to determine the “code,”or rule, that determines whetheror rule, that determines whetheror not a number is valid foror not a number is valid foroxygen production.oxygen production.

You should begin with a You should begin with a ““trial and error” typetrial and error” type

process that quickly leads youprocess that quickly leads youto form some kind of theoryto form some kind of theoryregarding what constitutesregarding what constitutes

““successful” numbers.successful” numbers.

Both successful and unsuccessfulBoth successful and unsuccessfulresponses should be recordedresponses should be recorded

to assist your evaluation.to assist your evaluation.

Works Doesn’t Work2,4,6, 1,3,5,

For example, these resultsFor example, these resultsmight suggest to some thatmight suggest to some thateven #’s work and odd #’s even #’s work and odd #’s do not.do not.

You must then go through aYou must then go through a““scientific” process of testing,scientific” process of testing,evaluation, and modificationevaluation, and modification

of your theories.of your theories.

This process should illustrateThis process should illustratewhat is commonly referred towhat is commonly referred to

as the “scientific method,”as the “scientific method,”along with many attributesalong with many attributesof the “nature of science.”of the “nature of science.”

This activity provides opportunitiesThis activity provides opportunitiesduring the entire process to illustrateduring the entire process to illustrateaspects of the nature of science.aspects of the nature of science.

Additional time should be taken atAdditional time should be taken atthe end of the exercise to reflect onthe end of the exercise to reflect onthe nature of science as evidenced bythe nature of science as evidenced bythis activity.this activity.

The following is a brief discussion ofThe following is a brief discussion ofhow this activity illustrates somehow this activity illustrates someaspects of the nature of science.aspects of the nature of science.

Scientific conclusions Scientific conclusions dependdepend on the creative imagination on the creative imagination ofof the scientist.the scientist.

aspects reinforced by this activityaspects reinforced by this activityinclude, but are not limited to:include, but are not limited to:

Nature of Nature of ScienceScience

Science is a social enterprise.Science is a social enterprise.

Scientific knowledge is Scientific knowledge is dynamicdynamic and subject to change.and subject to change.

Absolute certainty of aAbsolute certainty of a scientific conclusion is scientific conclusion is impossible.impossible.

Scientific conclusions dependScientific conclusions dependon the creative imaginationon the creative imagination

of the scientist.of the scientist.

• Participants were limited inParticipants were limited in their creativity by what theytheir creativity by what they had previously experiencedhad previously experienced with numbers.with numbers.

• Each participant looked at theEach participant looked at the exact same “evidence,” yetexact same “evidence,” yet depended on their own experiencesdepended on their own experiences and creative imagination toand creative imagination to determine the “reality” of whatdetermine the “reality” of what the numbers actually represented.the numbers actually represented.

This naturally led to differingThis naturally led to differing interpretations of the sameinterpretations of the same “ “reality.” reality.”

In what ways are the “creative”In what ways are the “creative”aspects of this activity similar toaspects of this activity similar to““creative” aspects of “real” science?creative” aspects of “real” science?

In what ways are they different?In what ways are they different?

How might prior experiencesHow might prior experiencesinfluence scientific interpretations?influence scientific interpretations?

Provide some possible examples.Provide some possible examples.

Science is a social enterprise.Science is a social enterprise.

• Because repeated failure wouldBecause repeated failure would be detrimental to the healthbe detrimental to the health of all, it was necessary forof all, it was necessary for participants to reach some typeparticipants to reach some type of consensus before attemptingof consensus before attempting a “trial.” a “trial.”

• Participants were forced toParticipants were forced to evaluate competing theoriesevaluate competing theories and determine the most plausible.and determine the most plausible.

• This decision may not have alwaysThis decision may not have always been made on the basis of meritbeen made on the basis of merit alone.alone.

In what ways are the social aspectsIn what ways are the social aspectsof this activity similar/different toof this activity similar/different tothe social aspects of “real” science?the social aspects of “real” science?

How are differences of opinionHow are differences of opinionsettled in scientific issues?settled in scientific issues?

Provide some possible examples.Provide some possible examples.

Scientific knowledge isScientific knowledge issubject to change.subject to change.

• A “theory” remains valid asA “theory” remains valid as long as it explains priorlong as it explains prior findings and is useful infindings and is useful in predicting new ones.predicting new ones.

• The “theories” were valid andThe “theories” were valid and useful until new “discoveries”useful until new “discoveries” proved them wrong.proved them wrong.

• Theories may undergo slightTheories may undergo slight change or total abandonmentchange or total abandonment when confronted withwhen confronted with discrepant evidence.discrepant evidence.

In what ways are the aspects of theoryIn what ways are the aspects of theorychange in this activity similar/differentchange in this activity similar/differentto the theory change aspects of “real”to the theory change aspects of “real”science?science?

How does one decide whether toHow does one decide whether toabandon or modify an existing theory?abandon or modify an existing theory?

Provide some possible examples.Provide some possible examples.

Absolute certainty of aAbsolute certainty of ascientific claim is impossible.scientific claim is impossible.

• No amount of trials could everNo amount of trials could ever prove one theory totally correct.prove one theory totally correct.

• Only one counterexample wasOnly one counterexample was needed to invalidate a theory.needed to invalidate a theory.

• No one will everNo one will ever know with absoluteknow with absolute certainty the truecertainty the true “ “rule” for therule” for the oxygen machineoxygen machine without seeingwithout seeing the “card.”the “card.”

In what ways are the uncertaintiesIn what ways are the uncertaintiesof this exercise similar/differentof this exercise similar/differentto that of “real” science?to that of “real” science?

What would “seeing the card” mean?What would “seeing the card” mean?

Will scientists ever “see the card?”Will scientists ever “see the card?”

Provide some possible examples.Provide some possible examples.

Aspects of the “Nature of Science”…Aspects of the “Nature of Science”…

Adapted from Adapted from Science for All AmericansScience for All Americans ( (link) and and Benchmarks for Science LiteracyBenchmarks for Science Literacy ( (link)

• The World Is UnderstandableThe World Is Understandable

• Scientific Ideas Are Dynamic and Subject To ChangeScientific Ideas Are Dynamic and Subject To Change

• Scientific Knowledge Is DurableScientific Knowledge Is Durable

• Science Cannot Provide Complete Answers to All Science Cannot Provide Complete Answers to All Questions (the “realm of science”)Questions (the “realm of science”)

• Science Demands and Depends on EvidenceScience Demands and Depends on Evidence

• Science Is a Blend of Logic and ImaginationScience Is a Blend of Logic and Imagination

• Science Explains and PredictsScience Explains and Predicts

• Scientists Try to Identify and Avoid BiasScientists Try to Identify and Avoid Bias

• Absolute Certainty of a Scientific Conclusion is Absolute Certainty of a Scientific Conclusion is Impossible (“Science Is Not Authoritarian”)Impossible (“Science Is Not Authoritarian”)

• Science Is a Complex Social ActivityScience Is a Complex Social Activity

• Science Is Organized Into Content Disciplines Science Is Organized Into Content Disciplines and Is Conducted in Various Institutionsand Is Conducted in Various Institutions

• There Are Generally Accepted EthicalThere Are Generally Accepted Ethical Principles in the Conduct of SciencePrinciples in the Conduct of Science

• Scientists Participate in Public Affairs Both as Scientists Participate in Public Affairs Both as

Specialists and as CitizensSpecialists and as Citizens

……Aspects of the “Nature of Science”Aspects of the “Nature of Science”

Adapted from Adapted from Science for All AmericansScience for All Americans ( (link) and and Benchmarks for Science LiteracyBenchmarks for Science Literacy ( (link)

What lessons can be learned from these activities What lessons can be learned from these activities that would help students get a better that would help students get a better

understanding of the “nature of science” (NOS)?understanding of the “nature of science” (NOS)?

The Rope TrickThe Rope Trick

The Human TangleThe Human Tangle

Activities: Activities:

Why should activities such as these be more Why should activities such as these be more likely to increase student understanding likely to increase student understanding

and achievement than other alternatives? and achievement than other alternatives?

The Oxygen MachineThe Oxygen Machine