Philosophy 150 Science and Human Culture September 8

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Philosophy 150 Science and Human
CultureSeptember 8

• Announcements
• Reading
• Kosso, pp 87-104
• Kosso, pp. 27 - 50
• Quiz 2 Wednesday
• Office Hours on Wed 9 - 10 and 1 - 2

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The H-D Method (complex version)

• Step 1 - Assert an Hypothesis
• Define initial conditions
• Assume relevant auxiliary theories
• Step 2 - Deduce necessary observational
  consequences
• If the hypothesis is true
• AND the proper initial conditions are set,
• AND the auxiliary theories are true,
• then the following observable event must occur.
• Step 3 - Check for those Observational
  Consequences.
• Conclude?

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Results of HD Testing

• If the expected observational consequences do
  occur, can we be certain the hypothesis true?
• Verification
• Problem of Underdetermination
• Verification comes in degrees
• Problem of induction

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Results of HD Testing

• Falsificationism
• The Null Hypothesis
• Crucial Experiment
• If the expected observational consequences do not
  occur, can we be certain the hypothesis is false?
• Einstein Example (see pg 73)

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Falsificationism

• Null Hypothesis Newtons Theory
• The speed of light is constant.
• C 299,792,458 m/s
• Light always travels in a straight line
• Gravity has no effect on light

• Hypothesis under test Einsteins Theory
• The speed of light is NOT constant
• Light can be affected by strong gravitational
  fields.

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Results of HD Testing

• If the expected observational consequences do not
  occur, can we be certain the Null Hypothesis is
  false?
• No, because of a different kind of
  Underdetermination.

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The H-D Method (complex version)

• Step 1 - Assert an Hypothesis
• Define initial conditions
• Assume relevant auxiliary theories
• Step 2 - Deduce necessary observational
  consequences
• If the hypothesis is true
• AND the proper initial conditions are set,
• AND the auxiliary theories are true,
• then the following observable event must occur.
• Step 3 - Check for those Observational
  Consequences.
• Conclude?

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Falsificationism

• Underdetermination (falsification)
• Maybe the initial conditions are wrong.
• Maybe there is some initial condition you failed
  to control
• May be one of your auxiliary theories is false

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So what are we to do?

• Falliblism
• Have testing as only PART of the process of
  theory assessment.
• Use Super-Empirical Values

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Evaluating Theories

• Is the theory a good scientific theory?
• Does the available evidence support the theory?
• Is it likely to be true given what we know about
  the universe?

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The virtues of a good theory

• Properties of a Good theory
• Properties that are truth conducting
• Properties that are accessible
• Not all of these properties need be accessed
  empirically.
• Good is a value judgment - thus it requires a
  set of shared values.

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Properties of a Good theory

• Values vs Virtues
• Constitutive Values
• Values generated by the goals of science itself
• Values embodied in the rules of acceptable
  scientific practice
• Contextual Values
• Values generated by the social, political,
  cultural context within which science is
  performed.

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Constitutive Values

• Internal Virtues - Properties of theories
  themselves. Indicators of coherence
• Entrenchment
• Explanatory Cooperation
• Testability
• Generality
• Simplicity

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Constitutive Values

• External Virtues - Properties of the relationship
  between the theory and the world. Indicators of
  correspondence
• Theories are about unseen causal structures, so
  correspondence cannot be directly assessed
• Explanatory Unification
• Testing and Confirmation

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Contextual Values

• What are some of the contextual values that
  influence science?
• Is science/should science be free from the
  influence of contextual values?
• Autonomy
• Integrity

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Conclusions

• Theories are always tested in groups, never in
  isolation
• Conclusive proof or disproof of a theory is
  impossible. Theories CAN be evaluated on a
  relative scale
• Observational evidence is insufficient for the
  evaluation of theories. Theory must be
  Empirically adequate, but that is not enough.