Chapter 7 - Critical Rationalism
Main Question: What is science?
Karl Popper and the Wiener Kreis
- Criticised Wittgenstein for being a dogmatist —> attacked Schlick (Vienna circle)
- Agreed with Logical positivism on importance of logical and mathematics and
emphasis on empirical testing
- But included rational aspect of fundamental importance
- Theory for him comes before, NOT after, observation
- Was a critical rationalist
Crucial Year, 1919
Popper’s clash with Marxism
- Said Marxism is Pseudoscience, no matter what happens its always right
- Learned 2 Lessons:
- Humans are liable to make mistakes, we are fallible creatures
- Major difference between dogmatic theories like the marxist theory of history and
critical thinking
Popper meets Alfred Adler
- Popper learned a theory is able to explain all the relevant data, if it is allegedly supported by
an “incessant stream of confirmations”, this is in fact a vice
- Experiences with both, made him question scientific value of theories that are able to
explain every possible observation —> Says, both are like astrology, in sense that these
theories are able of explaining everything but Unscientific
Popper and the bending of light
- Newtons idea overthrown by Einstein; They could be tested and refuted in a crucial test
- According to Einstein, rays of light bend more under influence of gravitational fields of large
objects than was predicted by Newton
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, - Deflection: part of starlight passes just alongside the sun would bend around the sun and
towards the earth, where we would then be able to see it
- The star would appear to us to be positioned not directly behind the sun, but
somewhat to one side of it
- Einsteins predictions were accurate
- Popper says, a theory cannot be considered scientific when it is always true
- Started to doubt the scientific status of theories that were able to explain each and every
observation
From verification, via confirmation, to falsification
- Main question: How to draw a boundary around science and set it apart from non-science ?
- Verification: Logical positivists proposal: too strong
- Cannot be adopted as a criterion for distinction, as newtons theory's not verified,
however this does not detract from its scientific character
- Core statements of science e..g universal laws cannot be verified, means that the best
of our sciences emerge as speculative nonsense if we follow logical positivists
- Verification is too strong as demarcation criterion, bc even prototypical scientific
disciplines like physics cannot be classified as science, the problem being that no
universal claim or law can ever be verified, for it is impossible to check every instance
that falls under that law
- Swan example: I cannot verify all swans are white, as id have to look at every living
swan
- Schlicks response: mere instruments
- Confirming evidence can be perceived everywhere
- The empirical base of verification is either:
A. certain but subjective (phenomalism)
B. intersubjective but not certain (physicalism)
Vienna Circle did not solve the problem about the foundation of scientific
statements
- a complete and definitive establishment of the truth (book, p. 206)
- is never possible; you can not observe everything
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, - Confirmation: Carnap proposal: too weak
- Disagreed with verifiability as its oversimplified and came up with confirmation
- Attempt to increase a statements degree of confirmation: A theory must be in
agreement with empirically established facts
- Science: A process of gradually increasing confirmation
- Swan: with every sighting of a white swan, the degree of confirmation of my theory
increases
- Falsification: Popper introduced 3rd way
- Disagreed with confirmability, as pseudosciences comet as better sciences
- Any legitimate scientific theory will make predictions that could in principle be
falsified
- If a theory fails to make predictions that might conceivably be. wrong, it is not
scientific theory
- Swan example: Use deduction, look for the specific non white swan cases
Falsification Characteristics
1. Falsifiability as accurate criterion of demarcation
- A theory has to be falsifiable in order to be scientific
- Real sciences falsifiable, whereas pseudo-sciences lack this potential of being wrong
- Example: It will either rain tomorrow or not —> Gives no information, therefore we need
statement to be falsifiable for it to have scientific meaning and to be able to have real
information
- Marxist theory: Why is it unscientific?
- It was scientific, as it could have been falsifiable however it was falsified
- Instead of accepting this, they changed their own theory, so that Russian revolution did
not refute them
- Conventionalist twist: Attempt to deflect criticism by making adjustments to a theory
- Freud’s oedipus complex: Oedipus myth
- Easily falsifiable: bc you have to only find one son who would not kill his father and
sleep with the mother
- Freud claims that any boy who doesn't have the urges is in denial
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, - Then its unfalsifiable as 2 scenarios seem possible :
- A boy says he wants to sleep with mom, or not - both confirm the theory
(Oedipus didn't want to but did in the end)
- No case that would contradict the theory
- Popper says this explanatory power was its major weakness, as its unscientific.
- Their formulation makes them always right
- They adjust the theory after observations
- Their theory explains everything
2. Only theories that can be falsified are informative
- Take weather forecast example: only if its falsifiable ergo. if i can be wrong that sun is
shining, i can make an informative statement
- there is no new information in predictions - falsification is impossible
- It only provides a sharp demarcation line between scientific and non-scientific NOT
between meaningful and meaningless statements
- ERGO: Oedipus contains meaningful but NONscientific sentences
- Responds to Charles Darwin saying the same - Started off as meaningful but
unscientific myth
3. Fallibility
- We do not know: we can only guess
- Humans are error-prone
- Limitations of biological make-up prevent us from ever attaining certainty
- All we can do: learn from our mistakes - grow by trying to locate & remove mistakes
- Negative Road to truth (Via negative)
4. Knowledge grows through conjectures and refutations, trial and error
- Induction is invalid
- Deduction is logically valid e.g. all men are mortal then do president is mortal
- Problem is to establish truth of first premise, the general statement
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