Scientific Method

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Scientific Method
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REASONINGtwo ways of thinking
INDUCTIVE THINKING
DEDUCTIVE THINKING

• identifies a patternconducts an
  investigationdevelops a rule (conclusion)
• specific to general
• used frequently in science
• ie. all sheep that Ive seen are white, therefore
  all sheep must be white

• begins w/ a general ruleapplies a situation to
  it
• general to specific
• used frequently in math
• ie. all turtles have shells the animal I have
  captured is a turtle, therefore I conclude the
  animal in my bag has a shell

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• ie. I have observed 10,000 dogs every one of
  them has fleas, therefore ALL dogs have fleas.
• ie. All dogs have fleas. This is a dog,
  therefore it must have fleas.

INDUCTIVE
DEDUCTIVE
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The Scientific Method
The scientific method is the procedure by which
scientists learn about the world.
Scientific knowledge begins with observations.
Direct observations can be made by seeing,
hearing, feeling, tasting, and smelling.
Through advances in technology we have been able
to extend our natural ability to observe.
Microscopes and satellites help us see.
Sonar helps us hear.
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A statement that might be true is called a
hypothesis.
A good hypothesis must be testable, or in other
words, easily proven false if it is in fact false.
An example of a bad hypothesis is, Aliens exist
somewhere in the universe.
While only a good hypothesis can be proven false,
no hypothesis can be proven absolutely true.
An example of a good hypothesis is, All fish
have gills.
Somewhere there may be a fish that doesnt
have gills and can disprove this hypothesis.
A hypothesis that has passed so many tests that
it is generally regarded as true is called a
theory.
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In order to test a hypothesis scientists can
1) rely on simple observations of nature.
2) or artificially create a situation...
this is called an experiment.
variable - a factor that might affect
observations.
By choosing to run an experiment instead of
making simple observations a scientist can
eliminate unwanted variables.
Variables that are kept constant and therefore
are prevented from affecting an experiment are
said to be controlled, and the experiment is said
to be a controlled experiment.
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The scientific method is limited by scientists.
Scientists can make errors. Scientists can be
bias.
The scientific method is also limited by science
itself.
Science cannot make judgments about values,
ethics, or morality. Science can reveal how the
world is but not how it should be.