Science

1
Science SWEDifferences and Similarities

• Amardeo Sarma

2
Basic Assumptions of Science

• Realism The world exists independent of our
  existence and perceptions
• Naturalism There exist natural causes for all
  phenomena
• Skepticism Our theories and assumptions are
  revisable in the light of new evidence no final
  truths

3
Basic Assumptions of Science

• Universalism Scientific theories are or should
  be independent of culture
• Testability Scientific theories must be testable
  by evidence and must have consistently passed
  tests
• Falsifiability There must be some way to show a
  theory is wrong

4
Illustration Anti-Science

• Supernaturalism Supernatural causes for
  phenomena
• Postmodernism Truth is relative
• Traditionalism Truth depends on the length of
  belief in something
• Constructivism (as a philosophy) Theories are
  just constructions of the mind

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Procedure

• Invent a hypothesis with good mathematics
• Empirists Induction
• Rationalists Just think
• Test the hypothesis based on observations of the
  real world (experience)
• Falsification more severe than verification
• After long successful testing the hypothesis
  becomes a tested theory
• A theory can be killed by new evidence

6
Software Engineering Assumptions

• All assumptions of science and scientific
  theories are valid
• Engineerability A partial world can be developed
  (constructed) according to our desires
• Specifiability Our desires can be formulated as
  a formal specification

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Software Engineering Assumptions

• Implementability A specification should lead to
  an implementation
• Conformance An implementation should work
  according to the specification

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Procedure (for good software engineering)

• Invent and agree on a Specification with good
  formalisms
• Create an implementation based on the
  specification
• Test the implementation based on observations of
  the partial real world (testing)
• Verification more important than falsification
• After long successful testing the implementation
  becomes a product
• A product can be killed if it doent work

9
Comparison

• The procedure is very similar
• Correspondence between hypothesis or
  specification with the (SWE constructed) real
  world is called for
• In science what is (the real world) is important
• In software engineering what we want is important

10
Constructivism doesnt work for SW engineering
either

• Imagine
• A car that just works for Europeans
• A compiler that creates different code for women
• A coffee machine delivers coffee if you use a
  German coin for a Swiss machine because you think
  it is a Swiss coin