Veni,%20Vidi,%20Induxi

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Veni, Vidi, Induxi
UC 2002 Fall
Ladyman Chapter 1-2

• Louis, Jessica, Sandra, Floris

Sci101 History Philosophy of Science
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Order of Appearance

1. Sandra (Background Information)
2. Jessica Louis (Discussion)
3. Floris (Gruesome Theories)
4. Louis Jessica (Discussion)

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Background Information

• Sandra

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Scientific revolution

• Aristotle
• deduction
• Bacon
• induction

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Deduction

• All M are P
• S is M
• S is P

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Induction

• M1, M2, M3, Mn are P
• All M are P

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Hume

• Addressed problems of induction
• Cause and effect

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Discussion

• Jessica Louis

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Hume says

• In each case, the moral is that a priori
  reasoning and argument gets us nowhere "it is
  only experience which teaches us the nature and
  bounds of cause and effect, and enables us to
  infer the existence of one object from that of
  another.

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Gruesome Theories
The role of theories in inductive science.

• Floris

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Topic Outline

• What are scientific theories?
• Characteristics, Inner Mechanics
• What can go wrong?
• The role of theories in inductive reasoning.
• The Grue-paradox

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Brainstorm

• Once again brainstorm about

Theory
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Theory Characteristics I

• A theory tries to explain why certain events take
  place.
• Example

I (Ptolemy) designed my theory about the solar
system to explain the observed movement of the
planets and stars.
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Theory Characteristics II

• How do they go about explaining?
• Compare
• This here is a chair. (hardly a theory)
• There is a force on this chair.
• Can we directly see a force?
• Only its results.
• Scientific Theories postulate things that cannot
  be directly perceived.

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Likewise,

• Likewise, a generalised
• rule cannot be perceived.
• Causal relation
• If I drop this chair out of the window, it will
  fall to the ground.
• We cannot directly see this rule in nature it
  rather is a pronunciation of our notion of
  regularity in accumulated perceptions of objects
  falling when dropped.

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Results

• Since we cannot directly perceive what a theory
  postulates, therefore, in order to verify the
  theory, we can only look at the perceivable
  predictions it makes.

Generalised Rules
Theoretical
Observations
X1 X2 X3 X4
Xa Xb
Theory (nice story)
explain
induction
Xc Xd
predict
Unperceivable Concepts
deduction
test X5
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Example
This thing falls, that thing falls to the ground.
This thing falls at a different speed.
Observation
Everything that is released falls to the ground.
In that case, things on the moon will fall at a
different speed.
Generalised Rule
Things fall because there is a gravitational
force being applied to it (depending on size of
attracting body).
Theory
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Problem about Scientific Theories

• But if the predictions are correct, then the
  theory does not have to be right (consider the
  fairy tale).
• Therefore, there are two kinds of problems
• We cannot verify all possible cases a theory
  covers. (Presented by Ladyman) (philosophy of
  science)
• We cannot verify the theory in itself.
  (metaphysics)

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Illustration Problem

• Being grue means being green before 2005 and
  blue after 2005.
• Now we have a theory that says that all emeralds
  are grue.
• Every emerald we see seems to add up to the
  conclusion that this theory is correct.

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Ockhams Razor

• William of Ockhams Razor
• If all things are equal, the most simple
  explanation is the right one.
• By the way, he was a Medieval Philosopher.

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Conclusions

• Scientific theories are designed to explain.
• Scientific theories tend to postulate concepts
  that cannot be directly perceived.
• Problems about induction
• We cannot verify all possible cases a theory
  covers. (presented by Ladyman)
• We cannot verify the theory in itself.

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Discussion

• Louis Jessica

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Science is the religion of modern societies
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Science is the religion of modern societies

• Definition of religion (the concise Oxford
  dictionary)
• The belief in a superhuman controlling power,
  esp. in a personal God or gods entitled to
  obedience and worship
• A particular system of faith and worship
• A thing that one is devoted to
• Et cetera

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Science is the religion of modern societies

• Since scientific theory in itself cannot be
  observed, therefore it could be just a likely
  explanation. It takes a leap of faith to believe
  that the theory is actually true.

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The End

• Have a nice break.

• A copy of this presentation is available for
  downloading at http//vanvugt.cjb.net