WHAT IS THE NATURE OF SCIENCE?

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WHAT IS THE NATURE OF SCIENCE?
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SCIENTIFIC WORLD VIEW

1. The Universe Is Understandable.
2. The Universe Is a Vast Single System In Which the
   Basic Rules Are Everywhere the Same.
3. Scientific Ideas Are Subject To Change.
4. Scientific Knowledge Is Durable.
5. Science Cannot Provide Complete Answers to All
   Questions.

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WHAT IS THE NATURE OFSCIENTIFIC INQUIRY?

• Certain features of science make it distinctive
  as a means of understanding the world/universe
• Those features are especially characteristic of
  the work of professional scientists, but anyone
  can use them to think scientifically about many
  aspects of everyday life

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Science Demands Evidence

• The validity of scientific claims is settled by
  referring to observations of phenomena
• Therefore, scientists concentrate on getting
  accurate data

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THE SCIENTIFIC METHOD

1. Observe and describe a phenomenon or group of
   phenomena.
2. Formulate hypotheses to explain the phenomena
   hypotheses often take the form of a proposed
   causal mechanism or mathematical relationship.
3. Use the hypotheses to predict the existence or
   actions of other phenomena, or to predict
   quantitatively the results of new observations.
4. Perform additional data collection or repeat
   experimental tests of the predictions by several
   independent experimenters using properly
   performed techniques or experiments.

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THE SCIENTIFIC METHOD

• Observations/Data ? Hypotheses ? Hypothesis
  Testing ? Models ? Laws ? Theories
• At some point in time, each stage must be
  reported to the larger scientific community by
  presentations or publications.

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THE SCIENTIFIC METHOD

• The scientific method does not allow any
  hypothesis to be proven true
• Hypotheses can be disproven, in which case those
  hypothesis are rejected as false
• A hypothesis which withstands a test designed to
  falsify it establishes a level of probability
  that the hypothesis accurately explains data and
  can be used for further predictions, subject to
  further tests

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Hypothesis Testing
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SCIENTIFIC LAWS AND THEORIES

• A Scientific Theory is an explanation of a set or
  system of related observations or events based
  upon proven hypotheses and verified multiple
  times by detached groups of unbiased researchers
• (One scientist cannot create a theory s/he can
  only create hypotheses)

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SCIENTIFIC LAWS AND THEORIES

• As a result of our confidence in the Scientific
  method, both scientific laws and broader
  scientific theories are accepted to be true
  (accurate) by the scientific community as a whole
  
• A scientific law or a scientific theory is used
  to make predictions of events or relationships
  among data sets

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SCIENTIFIC LAWS AND THEORIES

• The biggest difference between a law and a theory
  is that a theory is much more complex and dynamic
  
• A law governs a single action or situation,
  whereas a theory explains an entire group of
  related phenomena (Mendels Laws versus Darwins
  Theory of Evolution by Natural Selection)

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SCIENTIFIC LAWS AND THEORIES

• When the scientific community accepts a Law or
  Theory, it represents the best understanding of
  the explanations for the properties of a given
  system at that point in time
• A Scientific Theory represents our best
  understanding of the truth about some aspect of
  the universe, even though it is not proven as
  absolute and is still understood to be subject to
  future revision, or even to rejection

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THE EXPERIMENTAL METHOD

• The Experimental Method is usually considered the
  most scientific of all methods, the method of
  choice
• The main problem with all other non-experimental
  methods is less control over the situation and
  its components
• The Experimental Method exerts the most control
  on data collection and interpretation

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THE EXPERIMENTAL METHOD

• An experiment is a study of cause and effect
• It differs from non-experimental methods in that
  it involves the deliberate manipulation of one
  variable, while trying to keep all other
  variables constant
• Experiments must be properly designed and include
  controls

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HYPOTHESIS GENERATION

• The use of logic and the close examination of
  evidence are necessary but not usually sufficient
  for the advancement of science
• Scientific concepts do not emerge automatically
  from data or from any amount of analysis alone
• Inventing hypotheses or theories to imagine how
  the world works and then figuring out how they
  can be put to the test of reality is a creative
  thought process

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SCIENCE EXPLAINS AND PREDICTS

• Scientists try to make sense of observations by
  constructing explanations for observations that
  are consistent with currently accepted scientific
  principles
• Such explanationstheoriesmay be either sweeping
  or restricted, but they must be logically sound
  and incorporate a significant body of
  scientifically valid observations
• The credibility of scientific theories often
  comes from their ability to show relationships
  among phenomena that previously seemed unrelated

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SCIENCE EXPLAINS AND PREDICTS

• It is not enough for scientific theories to
  explain the observations that are already known
• Theories should also explain additional
  observations that were not used in formulating
  the theories in the first place that is,
  theories should have predictive power

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SCIENTISTS TRY TOIDENTIFY AND TO AVOID BIAS

• When faced with a claim that something is true,
  scientists respond by asking what evidence
  supports it
• But scientific evidence can be biased in how the
  data are interpreted, recorded or reported, or
  even in the choice of what data are considered in
  the first place
• A scientists nationality, culture, sex, ethnic
  origin, age, political convictions, etc., may
  incline him or her to look for or emphasize one
  kind of evidence or interpretation or another

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SCIENCE IS NOT AUTHORITARIAN

• In science, it is appropriate to turn to
  knowledgeable sources of information and opinion,
  usually specialists in relevant disciplines
• But respected authorities have been wrong many
  times in the history of science

Aristotle
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SCIENCE IS SELF CORRECTING AND PROGRESSIVE

• In the short run, new ideas that do not agree
  well with mainstream ideas may encounter vigorous
  criticism, and scientists investigating such
  ideas may have difficulty obtaining support for
  their research
• Challenges to new ideas are the legitimate
  business of science in building valid knowledge

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SCIENCE IS SELF CORRECTING AND PROGRESSIVE

• SF Author Sir Arthur C. Clarkes First Law When
  a distinguished but elderly scientist states that
  something is possible, he is almost certainly
  right. When he states that something is
  impossible, he is very probably wrong.

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SCIENCE AS A WAY OF KNOWING

• The Universe Is Understandable
• The Universe Is a Vast Single System In Which the
  Basic Rules Are Everywhere the Same
• Scientific Ideas Are Subject To Change
• Scientific Knowledge Is Durable
• Science Cannot Provide Complete Answers to All
  Questions
• Scientific ideas are developed by particular ways
  of observing, thinking, experimenting, and
  validating
• Observations/Data ? Hypotheses ? Hypothesis
  Testing ? Models ? Laws ? Theories