Structure of Scientific Revolutions, V

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Structure of Scientific Revolutions, V

• October 27, 2008

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Outline

• Theory change is real, non-cumulative change.
• Incommensurability (Language)
• Incommensurability (Standards)

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Objection to non-cumulativity

• Kuhn old theories completely replaced by new
  theories.
• Positivists old theories are simply special
  cases of new theories.
• Newtonian example
• Positivists special cases cant conflict with
  the more general theory.

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Objection to non-cumulativity

• Basic point properly understood, scientific
  theories are only about the sensations so far
  experienced.
• p. 99
• Newtons theory was only about the experiences
  the scientists had so far had, and it was correct
  for these. The newer Einsteinian theory goes
  further than Newtons, but it doesnt show
  Newtons to be false.

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Objection to non-cumulativity

• Q Is this the Positivist view?
• A Yes, for some (e.g., Schlick).
• Kuhns Objections
• On this view, no competent science is ever
  refuted.
• On this view, scientists should not be committed
  to theories outside their experiences.

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Objection to non-cumulativity

• Q Is this the Positivist view?
• A Not quite, for some (e.g., Ayer)

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Summing Up Kuhns Response

• New theories really are new. Science is not
  cumulative.

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Incommensurability (Language)

• Incommensurability impossible to measure or
  compare.
• Kuhn different theories are linguistically
  incommensurable.

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Incommensurability (Language)

• Holism about Meaning
• The meaning of a term is determined by its
  structural role in a language.
• Example God

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Incommensurability (Language)

• Newtonians and Einsteinians make very different,
  incompatible claims about mass.
• The theoretical context as a whole (the term and
  its role within a paradigm) determines the
  meaning of a term.-------------------------------
  --------------------
• Thus, the two sides mean something different by
  mass.

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Incommensurability (Language)

• Newtonian This has mass m.
• Einsteinian This has mass m.

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Incommensurability (Language)

• Consequences
• No neutral observation language to compare
  theories.
• Different theories arent rivals, since they
  literally deal with different empirical evidence.

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Incommensurability (Language)

• Sketch of an alternative
• Direct Reference
• The meaning of a term is determined by its
  referent.

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Structure of Scientific Revolutions, VI

• October 29, 2008

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Incommensurability (Standards)

• Kuhn the scientific standards of evaluation are
  relative to the paradigm that you adopt.
• paradigms provide scientists not only with a
  map but also with some of the directions
  essential for map-making. (p.109)

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Incommensurability (Standards)

• Digression on Relativism
• X is relative to Y.
• Morality is relative to your cultures standards.
• Truth is relative to what the majority believes.
• Beauty is relative to the observer.
• Tastiness of a dish is relative to ones
  preferences.
• Measurements of time are relative to ones
  velocity.
• Appropriate manners are relative to a culture.

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What you morally should do is relative to your
situation. Example there is a bicycle accident
and a cyclist is lying injured in the road. I am
nearby the accident, you are visiting your
parents in Florida. Jeff is morally obligated
to help the cyclist. You are not morally
obligated to help the cyclist.
IS THIS RELATIVISM?
What you should believe is relative to your
information. Example I have seen a weather
report that predicts a freak snowstorm in July.
The report is very reliable. You have not seen
the weather report. Jeff should believe that
there will be snow. You should not believe that
there will be snow.
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What you should do is relative to your
situation. What you should believe is relative to
your information.
Statements about what to believe/what to do.
The morality of your actions is relative to your
culture. The goodness of your beliefs is relative
to the standards of their culture.
Statements about standards for beliefs/actions.
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Incommensurability (Standards)

• Kuhn Scientific standards are relative to ones
  paradigm.
• The standards governing reasoning, evidence, and
  justification are relative to the paradigm in
  which one is situated.

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Incommensurability (Standards)

• Quote on p. 94.
• Q What is Kuhn saying?
• Q But arent there shared scientific standards?
• Example You must account for the data.

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Incommensurability (Standards)

• Normative vs. Descriptive Relativistic Theses

Descriptive people have different moral
rules. Normative different moral rules are
correct for the different people.
  Descriptive scientists in different
paradigms adopt different rules/standards of
good science. Normative different
rules/standards of good science are correct
for those people.
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Incommensurability (Standards)

• If we want to deny normative relativism, then
  there must be a way to judge paradigms.
• Kuhn there is no scientific way to judge
  paradigms.
• Q Is there any way to do so?
• The paradigm we have now is not closer to ideal
  paradigm than others.
• 2. In general, science is not heading towards
  an ideal paradigm.

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Incommensurability (Worlds)

• October 29 31, 2008

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Incommensurability (Worlds)

• Different Worlds Thesis scientists under
  different paradigms do their science in different
  worlds.

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The Gestalt Analogy
Mundane point different people can see the same
thing in different ways.
e.g., duck-rabbit, Necker cube, topo map, bubble
chamber, etc.
Interesting point the way you see things can be
determined by background theory, training, etc.
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Duck or rabbit?
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The Gestalt Analogy
Interesting point the way you see things can be
determined by background theory, training, etc.
Theory-laden Observation There is no neutral
way of seeing things. Every observation is
mediated by our expectations, beliefs, training,
etc.
No Different Worlds Thesis (DWT) from this.
Kuhn Nevertheless, when it comes to scientific
observation, DWT is true.
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No DWT.
DWT.
Why the difference?
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The Gestalt Analogy
Kuhn with the duck-rabbit, (i) we have the
experimenter assuring us the image hasnt
changed. (ii) we can see the image as an
unchanging set of lines (thus as neither a duck
nor a rabbit).
Kuhn but with science we dont have this
assurance. Q how does (i) help? Q how does
(ii) help? My Claim the duck-rabbit case isnt
different than the science case.
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Kuhns Argument

• At the very least, as a result of discovering
  oxygen, Lavoisier saw nature differently. And in
  the absence of some recourse to that hypothetical
  fixed nature that he saw differently, the
  principle of economy will urge us to say that
  after discovering oxygen Lavoisier worked in a
  different world. (118)

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Kuhns Argument
Data scientists see the world differently. Three
explanations of data (1) the world is the same
but their way of seeing is different, (2) they
see in the same way, but the world is
different (3) some mixture of (1) and (2).
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Kuhns Argument
Data scientists see the world differently. Three
explanations of data (1) the world is the same
but their way of seeing is different, (2) they
see in the same way, but the world is
different (3) some mixture of (1) and
(2). Kuhn option (2) is required by the
principle of economy.
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Kuhns Argument
(1) the world is the same but their way of
seeing is different, (2) they see in the same
way, but the world is different (3) some
mixture of (1) and (2).
(1) Scientists see things differently. (2) If
scientists inhabited different worlds, then that
would explain why they see differently. (C)
Thus, scientists inhabit different worlds (DWT).
Q What kind of argument is this? Q Why does
Kuhn think that the different worlds explanation
is the best explanation?
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On Behalf of Kuhn

• This is all metaphoricalIt is as if scientists
  lived in different worlds.
• But Until that scholastic paradigm was
  invented, there were no pendulums, but only
  swinging stones, for the scientist to see.
  Pendulums were brought into existence by
  something very like a paradigm-induced gestalt
  switch. (120)

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Commonsense View All scientists, if looking at
the same thing, have the same observation.
Kuhns Response This commonsense view is a
paradigm about to break down Thus, scientists
from different paradigms live in different
worlds.
Is there a middle road? Scientists can have
different observations when looking at the same
thing. But they really are observing the same
thing. Utilizing a psychological theory, we can
better understand what influences our
observations.
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Conclusion

• The operations and measurements that a scientist
  undertakes in the laboratory are not the given
  of experience but rather the collected with
  difficulty. (p. 126)
• A good philosophy of science will have to address
  this, and it had been neglected before Kuhn.
• So this is a shift. But not in the way Kuhn
  imagined.