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Imre lakatos

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The Philosophy of Science Imre Lakatos entitled "Science as Successful Prediction: Falsification and the Methodology of Scientific Research Program."

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IMRE LAKATOSSCIENCE AS

SUCCESSFUL PREDICTION:

“Falsification and the Methodology of Scientific Research

Program

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PROFILE(November 9, 1922 – February 2, 1974)born Imre (Avrum) Lipsitz to a Jewish family

in Debrecen, Hungarywas a philosopher of mathematics and sciencereceived a degree in mathematics, physics,

and philosophy from the University of Debrecen in 1944

He became an active communist during the Second World War

 He changed his last name once again to Lakatos (Locksmith) in honor of Géza Lakatos

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After the Soviet Union invaded Hungary in November 1956, Lakatos fled to Vienna, and later reached England. He received a doctorate in philosophy in 1961 from the University of Cambridge. The book Proofs and Refutations: The Logic of Mathematical Discovery, published after his death, is based on this work.

Lakatos never obtained British Citizenship, in effect remaining stateless.

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Science: Reason or Religion?

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For Centuries, Knowledge

meant Proven Knowledge.

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Popper- Falsifiability Method

- virtue lies not in caution in avoiding errors, but in ruthlessness in eliminating them (Freudan and Marxist Errors)

- Belief may be a regrettably unavoidable biological weakness to be kept under the control of criticism.

- Commitment is for Popper, an outright crime.

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KuhnRevolution is

exceptional, extra-scientific

Criticism is, in normal times, anathema.

Transition from Criticism to Commitment marks the point where progress and normal science begins.

New Theories only emerge where ``crisis`` begins

``Psychology of Discovery``Truth lies on powerReligious Change

Popper• Revolution is

permanence• Criticism is the heart

of the scientific enterprise

• “Logic of Discovery”

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Fallabilism vs. FalsificationismSophisticated versus Naive

Methodological Falsificationism.

Progressive and Degenerating Problemshifts

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Sophisticated versus Naive Methodological Falsificationism.

Differs from its rules of

acceptance (demarcation

criterion) and its rules of

falsification or elimination

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Naive Falsificationist Any theory which can

be interpreted as experimentally falsifiable, is "acceptable" or "scientific."

Sophisticated Falsificationist

• A theory is "acceptable" or "scientific" only if it has corroborated excess empirical content over its predecessor (or rival), that is, only if it leads to the discovery of novel facts.

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• This condition can be analyzed into two clauses: that the new theory has excess empirical content ("acceptability"1) and that some of this excess empirical content is verified ("acceptability"2). The first clause can be checked instantly by a priori logical analysis; the second can be checked only empirically and this may take an indefinite time.

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A theory is falsified by a "(fortified) observational" statement which conflicts with it (or rather, which he decides to interpret as conflicting with it).

• regards a scientific theory T as falsified if and only if another theory T' has been proposed with the following characteristics:

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(1) T' has excess empirical content over T: that is, it predicts novel facts, that is, facts improbable in the light of, or even forbidden, by T,

(2) T' explains the previous success of T, that is, all the unrefuted content of T is contained (within the limits of observational error) in the content of T'; and

(3) some of the excess content of T' is corroborated.

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T1 T2 T3Excess Empirical Content

PROGRESSIVE (or constitutes a theoretically progressive

problemshiftEMPIRICALLYPROGRESSIVE (or

constitutes an empirically progressive problemshift

New Fact!!

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PROBLEMSHIFT Progressive if both empirically and

theoretically progressiveAccept if they are at least theoretically

progressive“FALSIFIED”“Degenerating” if it is not.“Reject” if not and termed as

“Pseudoscience.”Progress is measured by the degree to

which a problemshift is progressive, by the degree to which the series of theories leads us to the discovery of novel facts. We regard a theory in the series "falsified" when it is superseded by a theory with higher corroborated content.

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A given fact is explained

scientifically only if a new fact s also explained

with it.

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Sophisticated Falsificationism Series of

Theories

Series of Theories

Theories

Series of

Only a series of theories can be

said to be scientific or

unscientific: to apply them the term "scientific"

to one single theory

is a category mistake.

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Revised Methodological Falsificationism Features:it denies that "in the case of a scientific

theory, our decision depends upon the result of experiments.

It denies that "what ultimately decides the fate of a theory is the result of the test, i.e., an agreement about basic statements.

Contrary to naive falsificationism, no experiment, experimental report, observation statement or well-corroborated low-level falsifying hypothesis alone can lead to falsification. There is no falsification before the emergence of a better theory.

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Falsification can thus be said to have a "historical character.”

Some of the theories which bring about falsification are frequently proposed after the "counterevidence."

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Thus the crucial element in

falsificationism is whether the new theory offers any

novel, excess information

compared with its predecessor and whether some of

this excess information is corroborated.

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Justificationist

Confirming

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Refutation

Naive

Falsifi

catio

nist

s

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Methodological Fasificationist

The rather rare excess information which are the crucial ones receives the attention.

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Falsification in the Sense of naive falsificationism Not sufficient condition for eliminating a

specific theoryFalsification is not necessary for

Sophisticated Falsification: a progressive problemshift does not have to be interspersed with ‘refutations.’

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Sophisticated Falisificationism“Proliferation of theories” is important

Stresses that the urgency of replacing any hypothesis by a better one.

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THE POPPERIAN VERSUS THE KUHNIAN RESEARCH PROGRAM

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KUHN

In Kuhn’s view there can be no logic, but only psychology of discovery.

Scientific revolution is irrational, matter of mob psychology.