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FALSE ASSUMPTIONS
CAN GET YOU IN TROUBLE

THE NATURE OF SCIENCE

 SYNOPSIS

 PRINCIPAL CONCEPT

 ASSOCIATED CONCEPTS

 ASSESSABLE OBJECTIVES

Students will....

 MATERIALS

1. Overhead projector (preferable, not required).

2. Short "stories" of events which tend to be misinterpreted due to our tendency to attach certain meanings to words. These are best printed in large letters on overhead transparencies for projection so the entire class can read them. Eleven examples are attached at the end of this lesson, in pdf format.

 TIME

 STUDENT HANDOUTS

 TEACHING STRATEGY

1.  Introduce these early in the course, as part of your treatment of the nature of science. They fit nicely near the end of the period, as they are engaging and flexible in their timing.

2. Additional stories can be shared and solved at odd times throughout the course, partly as a reminder and reinforcement of the concept, and partly as something intriguing and fun. A nice way to close a period, and add variety to your class.

PROCEDURES

1. Explain to students that you are going to display a short story on the overhead, and read it to them as they read along. Point out that their challenge is to solve the mystery, but they can only ask questions (one at a time) which can be answered with a "yes" or "no", and you will answer those questions truthfully.

2. Show and read the first story. Keep the "Answer" and "False Assumption" covered. Answer their yes/no questions until someone asks the key question (the answer, phrased as a yes/no question), and you will answer "yes".

3. When it is solved, ask the class what the false assumption was. Tell the class to jot down examples of false assumptions which they/we make in our daily lives, to share with the class later. Also, ask them to think about (and record) what kinds of false assumptions scientists have made, the problems this created, and how they solved the problems.

An example of this might be the ancient assumption that the stars, sun, planets and moons all move around the earth. This geocentric model required the construction of complex orbits of planets and moons to explain their observed motions. Ptolemy's version (150 AD) used off-center orbits to accomplish this, but it seemed to be the most useful model for about 1400 years, even though it was based on a false assumption.

In 1543, Copernicus published his views that our planetary system should be heliocentric, with all bodies moving around the sun. He was able to show this mathematically, but he assumed that only circular orbits could be used for a perfect system (a deeply held assumption from classic Greek science), so his planetary orbits were as complex as Ptolemy's. But Galileo's discovery (1610) of phases for Venus did support the Copernican heliocentric theory. Eventually, Kepler (1619) figured out that elliptical orbits worked much better than circular orbits, so he modified the Copernican system by using elliptical orbits, resulting in the much simpler model that we have today.

Cutting through the assumptions of an earth-centered system and circular orbits has led to the modern view of our Solar System that has enabled us to predict planetary movements and fly space probes to very accurate encounters with each of our planets. Similar stories exist for the assumed causes of disease, behaviors, weather, etc. Things are not always as they seem! "Perception is NOT always REALITY!" (tipping your hat to a popular Mercedes Benz ad). I made a large banner of that "Perception..." quote and posted it in my room. It's amazing how many times arose when I conspicuously and knowingly glanced over to the poster to make the point...
For a lesson on this site that probes more deeply into this idea that "Perception is Not Always Reality" - click on that title.

4. Point out that one of the strategies of science is to recognize how easy it is to make false assumptions about the workings of nature, and to devise methods for avoiding or revealing those false assumptions for what they are. This often requires a total paradigm shift...a different way of looking at the situation, in which common assumptions are critically challenged, on purpose. Encourage you students to "think outside the box" and be cleverly creative.

FIRST STORY:

There is a cabin on the side of a mountain. Three people are inside and they are dead. How did they die?

Answer: They died in an airplane crash.
The False Assumption: the cabin is a log cabin. Actually, it is the cabin of a 747 jetliner. The dead are the pilot, co-pilot, and navigator.They crashed during a snow storm.

SECOND STORY:

It is hot August afternoon. The location is the living room in an old Victorian mansion. The 7-foot window is open and the curtains are blowing in the breeze generated by the thunderstorm that just passed. On the floor lie the bodies of Bill and Monica. They are surrounded by puddles of water and broken glass. Please close your eyes and picture the scene. Now change the picture. Neither Bill nor Monica has any clothing on. How did they die?

Answer: The wind blew open the windows, knocking over the fish bowl in which Bill and Monica had been swimming. The fish bowl crashed to the floor and broke, leaving Bill and Monica to suffocate without their water.
The False Assumption: that Bill and Monica were human. They were actually two goldfish.

 ASSESSMENT

 EXTENSIONS

& VARIATIONS

 Ask students to find and/or make up some similar "False Assumption" stories. Winning entries could win bonus points, or some other little "prizes", if you like. Then you could use them in other classes, or next year.

Here are a couple of examples:

1. A man rides in on Friday, stays 3 days, then leaves on Friday. How did he do that? (ANS: "Friday" is the name of his horse.).

2. How do you get down off a duck? (ANS: You pluck it.)

3. This might be a good time to play the Abbott & Costello routine "Who's on first", with its hilarious use of this kind of play on words.

Talking about false assumptions would also be a good time to bring out natural illusions, and how science is so effective in exposing the realities of those illusions (e.g. Procedure #3 above).

 OTHER RESOURCES

 ATTRIBUTIONS

Some of the ideas in this lesson may have been adapted from earlier, unacknowledged sources without our knowledge. If the reader believes this to be the case, please let us know, and appropriate corrections will be made. Thanks.

 1. Original Source: Steve Randak

2. Modified by:

3. ENSI / SENSI original developed by:

4. Reviewed / Edited by: Martin Nickels, Craig Nelson, Jean Beard 12/15/97

5. Edited / Revised for website by L. Flammer 8/98

 The following pages are in Adobe Acrobat pdf format in order to maintain their intended layout for showing on overhead projector. Only the first page is showing. To access all 11 pages (for printing and making transparencies), you will need to download the free Acrobat Reader from Adobe (unless it's already installed in your system). Then just click on the blue file name at the bottom of the first page. You will see the "Acrobat Exchange" application loading, then the pages will display. You might need to shift-click and drag the lower left corner of the page to enlarge it.