Downtown Campus Biology > Biology 181 > Lesson 1 Activities > What is Science? - Page 2

You could have had multiple hypotheses. My second hypothesis is that the light bulb is burned out. I replace the bulb and find that the lamp works. This result indicates that my second hypothesis was supported. If the lamp still didn’t work with a new bulb, my second hypothesis is rejected.

Limits of Science

Through science we learn a great deal about how the natural world functions, including our own bodies. However, not all questions can be answered scientifically. Some questions are a matter of opinion or faith. Some questions defy experimentation. If you cannot create a hypothesis and conduct an experiment or observation to test the hypothesis, the question cannot be answered scientifically.

Which questions can be answered scientifically? In other words, Which of the following statements could be supported or rejected using the scientific method?

1. Toast always falls with the buttered side down.
2. My dogs are cuter than any other dogs.
3. Leaves are green because they contains the pigment chlorophyll.
4. Hitler was an evil man.

Please fill in your initial guesses on your worksheet

A few words to help answer the questions above:

1. Beginning with the observation that toast always seems to fall buttered-side down, you generate the hypothesis "Toast always falls with the buttered side down."

Can you design an experiment to test this? Yes, there are multiple ways to test this hypothesis. For example, we could drop a piece of toast 100 times and determining how many times it falls butter-side down. If the toast fell butter-side down 100 times, the hypothesis is supported. If the toast fell butter-side up even one time, the hypothesis is rejected.

2. The statement "My dogs are cuter than any other dogs" is an opinion. This is not a hypothesis that can be tested scientifically.

However, we could do a survey to determine how many people agreed or disagreed with this statement. Our hypothesis could be "Most people think that my dogs are cuter than any other dogs." We could survey people and determine whether this hypothesis was supported or rejected.

3. Beginning with the observation that leaves are green, you generate the hypothesis "Leaves are green because they contain the pigment chlorophyll."

4. The statement "Hitler is an evil man" is an opinion. This statement cannot be answered scientifically. Like the "cute dogs" statement, we could do a survey to see how many agree with the statement.

Were your initial guesses about these four statements correct. If not, please mark your changes on your worksheet.

On your worksheet, please write two statements that could be tested scientifically and two statements that are a matter of opinion.

The question of proof

Some critics will tell you "Science can’t prove anything". In one respect, they are correct. The scientific method supports or rejects hypotheses. A hypothesis can be disproven, but never 100 % "proven", just supported.

Let's look at the statement: "Smokers get lung cancer more often than non-smokers".

Dozens of research studies show that smokers have a higher percentage of lung cancers than non-smokers. This hypothesis has been strongly supported. However, scientific experimentation can’t directly prove that smoking caused lung cancer in a particular person.

How much evidence is enough?

If enough evidence supports a hypothesis, and little or no evidence rejects it, the hypothesis is generally accepted as true. In the case of lung cancer, years of research lead the surgeon general to print warnings on cigarettes packages indicating "smoking may be hazardous to your health".

How much scientific evidence is enough for a person or society to take action on an issue, though, is a matter of opinion (and politics).

page 1 | page 2

Return to Lesson 1 Activities