The Scientific Method

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The Scientific Method
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Goal

• What is the scientific method?
• What does the scientific method assume?
• Does the scientific method work?
• What is not a scientific argument.
• Do things like astrology follow the scientific
  method?

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What is the scientific method?

• Science is a tool the goal is to learn how the
  world works.
• Biology What happens to surface water flow
  rates when a forest is clear-cut?
• Stop cutting the trees.
• Consult your neighbourhood astrologer.
• Pray to the god Xintahlopol, sacrifice a goat,
  roll the bones.

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The scientific method
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The Scientific Method

• Observe an event.
• Develop a model (or hypothesis) which makes a
  prediction.
• Test the prediction.
• Observe the result.
• Revise the hypothesis.
• Repeat as needed.
• A successful hypothesis becomes a Scientific
  Theory.

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Biological Science
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Everyday Science
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Everyday Science
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Food Science

• Hypothesis ? throwing something together to see
  if it works. May have to try this many times
  before kids will eat your cooking.
• Scientific Theory ? your grandmothers
  time-tested recipe

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Repeatability

• A successful theory is repeatable.
• By you.
• By anyone.
• Example of bad science
• Cold Fusion (1989) Stanley Pons Martin
  Fleischman.
• PS. Hey guys, this is why we have the peer review
  method.

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Requirements underlying the Scientific Method

• Objective reality
• We all see the same world.
• Constant Laws of Nature
• What happens here, happens there.
• What happened yesterday will happen tomorrow.
• The Cosmos is knowable.

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Does it work?

• Scientific Method is a tool.
• Does this tool work?
• Life expectancy
• Mortality rates
• Are there better tools?

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Recap Theories, Guesses, Laws

• What does the word Theory mean to you?
• A conjecture guess (Websters Dictionary)
• Does it mean the same to a scientist?
• A model which has been born out by repeated
  tests and observation.
• Is a Theory less than a Law?
• Evolution is just a theory, it is not a fact.
• Do Theories grow up to be Laws?
• Einsteins Theory of Relativity

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Theories

• So a theory is a highly successful hypothesis.
• All hypotheses make predictions.
• All theories make predictions.
• All theories can be tested.
• Result Any scientific theory is subject to
  change as our ability to make tests, or make
  observations of a tests results, improves with
  time.

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Non-scientific Theories

• Make no predictions.
• Are un-testable.
• Cannot be falsified.

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Non-scientific Theories

• Car wont work? ?
• Aliens drained the battery.
• Spaghetti is bland? ?
• You were meant to eat bland food.
• Car wont work? ?
• Gods must be angry.
• Spaghetti is bland? ?
• At the instant of tasting, tongue is transported
  to alternate dimension where all flavors are
  rendered nullified. Happens instantaneously.

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Non-scientific Theories

• The chain of events needed for life to arise is
  too complicated to have happened by chance, a
  divine intelligence must therefore have caused
  life to arise (Intelligent Design).
• Face on Mars.
• Astrology.

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Non-scientific Theories
Conjecture and theorizing without looking towards
the available evidence.
Subjecting the same set of data to new tests,
i.e. better imaging systems.
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Falsification

• A real Scientific Theory tells you what
  observations are necessary to falsify it.
• Not so proponents of
• Face on Mars
• Moon Hoax
• Intelligent Design
• Astrologers