What is What is “Inquiry in the Natural World”?“Inquiry in the Natural World”?
Clare 102 - Inquiry in the Natural WorldClare 102 - Inquiry in the Natural World
Ted GeorgianTed Georgian
19 January 200519 January 2005
Natty-world is a great course - really!Natty-world is a great course - really!
Two simple questions:Two simple questions:
1.1. What is the “natural world”?What is the “natural world”?
2.2. What does it mean to “inquire” about it?What does it mean to “inquire” about it?
What is the “natural world”?What is the “natural world”?
http://www.howardhallis.com/artgallery/tpoe/index.html
What’s a “physical object”?What’s a “physical object”?
http://the.honoluluadvertiser.com/article/2002/Dec/10/ln/ln12a.html
Is “love” a physical object”?Is “love” a physical object”?
Are there physical objects that we can’t sense?Are there physical objects that we can’t sense?
Dogs know who’s been Dogs know who’s been at the fire hydrantat the fire hydrant
Are there physical object that we can’t sense?Are there physical object that we can’t sense?
Do Honey bees see objects that we can’t? Do Honey bees see objects that we can’t?
Medical and Scientific Photography: An online resource for doctors, scientists and students (http://msp.rmit.edu.au/Article_01/13.html)
Are there physical objects that we can’t sense?Are there physical objects that we can’t sense?
Modern instruments have greatly Modern instruments have greatly extended our detection abilitiesextended our detection abilities
Can we make predictions about the natural Can we make predictions about the natural world?world?
Given a knowledge of the Given a knowledge of the “laws” of physics, can “laws” of physics, can you predict where this you predict where this car will go if you release car will go if you release the parking brake? the parking brake?
Can we make predictions about the natural Can we make predictions about the natural world?world?
Given the same knowledge of Given the same knowledge of the “laws” of physics, can the “laws” of physics, can you predict where a car will you predict where a car will go if it’s hijacked by a 14-go if it’s hijacked by a 14-year old?year old?
What’s “inquiry” in the natural world?What’s “inquiry” in the natural world?
Scientists ask a lot of questions, like kidsScientists ask a lot of questions, like kids
Some common questions Some common questions kids ask:kids ask:
Why is the sky blue?Why is the sky blue?
Where do babies come from? Where do babies come from?
Why does the moon follow my Why does the moon follow my car? car?
And my favorite:And my favorite: How can a brown cow How can a brown cow
eat green grass and eat green grass and make white milk?make white milk?
home.att.net/~rwskinner/ pictures/brown-cow-2.jpg
Two different sorts of answersTwo different sorts of answers
1. 1. DescriptionsDescriptions
“The sky is dark blue.” “The sky is dark blue.”
2. Explanations
“The sky is blue because …”
http://www.albforumi.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=16;t=000024;p=
www.sciencemadesimple.com/ sky_blue.html
Why inquire into the natural world?Why inquire into the natural world?
Two fundamental reasons: Two fundamental reasons: CuriosityCuriosity Problem solving
Curiosity-driven scienceCuriosity-driven science
Serena Parente Charlebois
Basic or “pure”Basic or “pure”
Often leads to surprisingly Often leads to surprisingly practical discoveriespractical discoveries
Lasers
X-rays
Teflon
DNA
Flubber (?)
Problem-solving scienceProblem-solving science
Applied or “practical”Applied or “practical”
Gives us substantial power Gives us substantial power over the natural worldover the natural world
Weapons
Computers
Contraceptives
Transgenic crops
Internal combustion
engines
Problem-solving scienceProblem-solving science
http://www.colostate.edu/programs/lifesciences/TrangenicCrops
Why do physical objects behave the way Why do physical objects behave the way they do?they do?
Anthropomorphic Anthropomorphic explanation explanation
Why do physical objects behave the way Why do physical objects behave the way they do?they do?
Mechanistic Mechanistic explanation explanation
A complex and very general explanation is A complex and very general explanation is often called a “Model”often called a “Model”
http://www.metaresearch.org/cosmology/cosmology.asp
www.prometheus-delft.org/ Isaac%20Newton.jpg
Isaac Newton’s model of “Universal Gravitation”
darwin.apnet.com/ www/ap/newton.htm
Newton’s model of “Universal Gravitation” has been very successful
Buffalo News, 13 Jan 2005, A8
CAPE CANAVERAL, Fla. - A NASA spacecraft with a Hollywood name - Deep Impact - blasted off Wednesday on a mission to smash a hole in a comet and give scientists a glimpse of the frozen primordial ingredients of the solar system. With a launch window only one second long, Deep Impact rocketed away at the designated moment on a six-month, 268 million-mile journey to comet Tempel 1. It will be a one-way trip that NASA hopes will reach a cataclysmic end on the Fourth of July.
Nothing like this has ever been attempted before. Little is known about comet Tempel 1, other than that it is an icy, rocky body about nine miles long and three miles wide.
Craft launched to dive into comet By MARCIA DUNN Associated Press1/13/2005
How do we investigate physical objects?How do we investigate physical objects?
perl.plover.com/yak/ regex/samples/slide004.html perl.plover.com/yak/ regex/samples/slide004.html www.geocities.com/ jkostaras/big_ben.jpg
What are physical objects made of?What are physical objects made of?
Here’s one early idea – “atomism”(Leucippus and Democritus, ~ 500 BC)
Trefil, J. & R. M. Hazen. The Sciences. 2nd ed. P. 163
What are physical objects made of?What are physical objects made of?
Here’s an alternate view – “elementalism”Here’s an alternate view – “elementalism”
http://astsun.astro.virginia.edu/~jh8h/Foundations/chapter2.htmlhttp://astsun.astro.virginia.edu/~jh8h/Foundations/chapter2.html
Aristotle (384 – 322 BC)Aristotle (384 – 322 BC)
Aristotle’s “model” of physical objectsAristotle’s “model” of physical objects
Here’s how it worked:Here’s how it worked:
http://www.chem.uidaho.edu/~honors/history.htmlhttp://www.chem.uidaho.edu/~honors/history.html
Aristotle’s “model” was widely accepted as Aristotle’s “model” was widely accepted as “true” from ~ 300 B.C. until ~ 1700s“true” from ~ 300 B.C. until ~ 1700s
Atomism was revived in the 1800sAtomism was revived in the 1800s
John Dalton, 1808.
A New System of Chemistry
How do scientists decide which explanations How do scientists decide which explanations are best?are best?
Democritus Aristotle
The “hypothetico-deductive” scientific methodThe “hypothetico-deductive” scientific method
More of a description of what usually works than a set of directions that every
scientist follows
Still – no better way of investigating the natural world has been invented in
the past 400 years
Francis Bacon (1561-1626)Francis Bacon (1561-1626)
Stressed observation over philosophical speculation
Proposed a new method of studying nature
Argued that if we understand nature we can dominate it
Steps in the scientific methodSteps in the scientific method
Step 1: ObservationsStep 1: Observations
Steps in the scientific methodSteps in the scientific method
Step 1 a: decide what to studyStep 1 a: decide what to study
Too much
Better
http://svdp.org/santaclara/images/Car_Lot.jpg
Steps in the scientific methodSteps in the scientific method
In western New York, cars in winter!
http://www.bigfoto.com/themes/nature/winter/
http://www.heatherandpatrick.com/Kitten-Library/details.php?photoID=194
http://www.budinas.narod.ru/current/winter4/winter4e.htm
How can we answer our questions about the How can we answer our questions about the natural world?natural world?
This step uses a process calledThis step uses a process called
Inductive ReasoningInductive Reasoning
in which we develop a rule based on many individual examples in which we develop a rule based on many individual examples
Step 1b: look for a general patternStep 1b: look for a general pattern
Steps in the scientific methodSteps in the scientific method
Step 1b: look for a general patternStep 1b: look for a general pattern
http://emd.wa.gov/5-ppt/trng/pubed/winterprep/starting-car-cold.htm
How can we answer our questions about the How can we answer our questions about the natural world?natural world?
A useful hypothesis: A useful hypothesis: 1.1.
2.2.
3.3.
Step 2: Think up explanations (hypotheses) Step 2: Think up explanations (hypotheses) for the patterns observed for the patterns observed
Steps in the scientific methodSteps in the scientific method
Step 2: Think up explanations (hypotheses) Step 2: Think up explanations (hypotheses) for the patterns observed for the patterns observed
1. Car won’t start because the coolant is frozen solid.
2. Car won’t start because the battery is too weak.
3. Car won’t start because it wants to be in Florida and it’s sulking.
4. Car won’t start because snow banks are actually alien spaceships
and the aliens have ray guns that disable cars.
Ockham’s “Razor”Ockham’s “Razor”
Start with the simplest possible Start with the simplest possible explanation and go to more complex explanation and go to more complex
explanations only if the simpler explanations explanations only if the simpler explanations don’t work.don’t work.
William of Ockham (1280 – 1347)
But the natural world isn’t necessarily But the natural world isn’t necessarily simple!simple!
“Make everything as simple as possible, but not simpler."
-- Albert Einstein (1879-1955)
sprott.physics.wisc.edu/ images/einstein.jpg
Steps in the scientific methodSteps in the scientific method
How can we tell which hypothesis is a better How can we tell which hypothesis is a better explanation of our observations?explanation of our observations?
These two seem like reasonable hypotheses:
• Car won’t start because the coolant is frozen solid.
• Car won’t start because the battery is too weak.
How can we answer our questions about the How can we answer our questions about the natural world?natural world?
This step uses a process calledThis step uses a process called
Deductive reasoning Deductive reasoning
in which we use the rules of logic in which we use the rules of logic to generate a predictionto generate a prediction
Step 3: Make a testable predictionStep 3: Make a testable prediction
Steps in the scientific methodSteps in the scientific method
IFIF the trouble starting the car is caused the trouble starting the car is caused by the coolant being frozen,by the coolant being frozen,
Step 3: Make a testable predictionStep 3: Make a testable prediction
THEN THEN we should see ice when we we should see ice when we open the radiator cap.open the radiator cap.
Steps in the scientific methodSteps in the scientific method
A good experiment:A good experiment:
1.1.
2. 2.
3.3.
Step 4: Make observations or do Step 4: Make observations or do experiments to test our explanations experiments to test our explanations
Steps in the scientific methodSteps in the scientific method
Step 4: Make observations or do Step 4: Make observations or do experiments to test our explanations experiments to test our explanations
Observation: open the radiator cap and look.Observation: open the radiator cap and look.
Result: antifreeze is fine – not frozen.Result: antifreeze is fine – not frozen.
Now what???Now what???
Start Start
over over
again!again!
Steps in the scientific methodSteps in the scientific method
IFIF the trouble starting the car is caused by the trouble starting the car is caused by the battery being weaker at low the battery being weaker at low temperatures,temperatures,
Step 3: Make a testable predictionStep 3: Make a testable prediction
THENTHEN replacing the battery should replacing the battery should enable the car to start on cold enable the car to start on cold morningsmornings
Steps in the scientific methodSteps in the scientific method
Step 4: Make observations or do Step 4: Make observations or do experiments to test our explanations experiments to test our explanations
ObservationsObservations: use a voltmeter to test the : use a voltmeter to test the battery each time the car won’t startbattery each time the car won’t start
ExperimentExperiment: try a new battery: try a new battery
Good experiments have:Good experiments have:
Replication Replication The experiment needs to be repeated by other The experiment needs to be repeated by other people on many other cars before we can be people on many other cars before we can be sure it’s generally reliable.sure it’s generally reliable.
ControlsControls
Need 2+ Need 2+ identical carsidentical cars
Experimental car: remove old battery and install a new one.
Control car: remove old battery and reinstall it.
How can we test Aristotle’s model?How can we test Aristotle’s model?
http://www.chem.uidaho.edu/~honors/history.htmlhttp://www.chem.uidaho.edu/~honors/history.html
Aristotle (384 – 322 BC)Aristotle (384 – 322 BC)
What predictions does it make?What predictions does it make?
D. Park. 1988. The How and the Why: An essay on the origins and development of physical theory. Princeton University Press, p. 49
According to Aristotle, each element has a According to Aristotle, each element has a natural resting place, and will return to itnatural resting place, and will return to it
Here’s an exampleHere’s an example
What’s mud made of?What’s mud made of?
Here’s another exampleHere’s another example
Observations: at first bubbling liquid Observations: at first bubbling liquid comes out of the end of the wood, comes out of the end of the wood, then yellowish flames leap up, then yellowish flames leap up, releasing light and heat. releasing light and heat.
When the fire goes out, gray ash When the fire goes out, gray ash remains at the bottom of the remains at the bottom of the fireplace. The ash helps plants fireplace. The ash helps plants grow in the garden.grow in the garden.
What happens when wood burns?What happens when wood burns?
What happens when wood burns?What happens when wood burns?
Explanation: wood is a Explanation: wood is a mixture of mainly Earth and mixture of mainly Earth and Fire, with varying amounts Fire, with varying amounts of Air and Water.of Air and Water.
When wood burns, the Fire When wood burns, the Fire escapes as flames and escapes as flames and rises to its natural resting rises to its natural resting place, leaving behind ash, place, leaving behind ash, which is mostly Earth and which is mostly Earth and so nourishes plants.so nourishes plants.
How can we decide if this model is a How can we decide if this model is a good scientific explanation?good scientific explanation?
1.1. Let’s not burn down Let’s not burn down Murphy HallMurphy Hall
2.2. Pick an easier object to Pick an easier object to study: waterstudy: water
3.3. Do experiments rather Do experiments rather than just observethan just observe
What does Aristotle’s model predict?What does Aristotle’s model predict?
1.1. If the electric current If the electric current heats the Water, it heats the Water, it should produce “Air”should produce “Air”
2.2. The resulting Air The resulting Air should riseshould rise
3.3. Pure Water should Pure Water should produce only one produce only one type of Airtype of Air
Here’s what the experiment looks likeHere’s what the experiment looks like
What actually happens?What actually happens?
Results:Results: ““Air” from one tube Air” from one tube
floats, one sinks floats, one sinks
One is flammable, One is flammable, one isn’t one isn’t
Conclusion: two different types of Air were produced
What do we do now?What do we do now?
1.1. Give up and go to Give up and go to work at McDonaldswork at McDonalds
"The great tragedy of Science—the slaying of a beautiful hypothesis by an ugly fact." Thomas Huxley
2.2. Modify the hypothesisModify the hypothesis
3.3. Develop a better Develop a better explanation of the explanation of the nature of matternature of matter
Here’s another model of waterHere’s another model of water
The mechanical model of the 1800sThe mechanical model of the 1800s
So: is this the right answer?So: is this the right answer?
Not since ~1900! Stay tuned for details later.
How does science make progress?How does science make progress?
1.1. Occurs in Occurs in cyclescycles
2.2. Gradually Gradually eliminates poor eliminates poor explanations, explanations, but ...but ...
3.3. The process is The process is never complete.never complete.
M. Johnson. 2003. Human Biology. 2nd ed. Benjamin Cummings.