Unit 3 Revolutions and

relativism

So far:

• Logical positivism and confirmation• Critical rationalism (Popper) and falsification• Today: sociology of science

• In the sixties and seventies of the last century a new generation of philosophers of science emerged. – Thomas Kuhn (1922-1996) – Paul Feyerabend (1924-1994)– Imre Lakatos (1922-1974)

Thomas Kuhn

• Popper was describing the way science ought to work (normative)

• Thomas Kuhn was interested in the way science actually works (descriptive)

• Popper and the logical positivist made a rational reconstruction

• They focus on the reasons not the causes for scientific behavior.

Take a game of chess

• The rules of the game are internal to the game

• Your motives four playing a game of chess are however external

Conceptual frameworks

• Facts do not really speak for themselves• Facts are part of a conceptual framework• Kuhn calls such a conceptual framework a

paradigm

paradigms

The pre-paradigmatic

period

The pre-paradigmatic period

• The pre-paradigmatic period is the period before there is a paradigm.

• There is confusion among ‘scientists’ because they do not share a common paradigm.

• Scientist think differently about what facts are and what are important problems.

The pre-paradigmatic

periodnormal science

Normal science as puzzle solving

• Normal science begins when a scientist comes up with a new and interesting view, a model.

• After a paradigm is established, researchers can agree on the problems and facts.

Anomalies

• If an anomaly occurs it is not the problem of the paradigm but of the scientist.

• Ad hoc adjustments• No falsification: Scientist are dogmatic

The pre-paradigmatic

period

normal sciencecrisis

Crisis

• If to much anomalies occur there is a crises• Confusion returns, and the old paradigm starts

to crumble.• Two solutions:

1. The issues are resolved2. A new paradigm is found, revolution.

The pre-paradigmatic

period

normal science

crisis

revolution

Revolution

• New (young) scientist come up with a fresh idea.

• A paradigmatic shift occurs (Gestalt-switch), a change of worldview.

Paradigms are incommensurable

Assignment

• Think of three examples you consider paradigm shifts

• These examples could about science, society, or your own life

• Present it in front of the group

progress

• why does science progress?• how does it progress?• and what is the nature of its progress?

• Kuhn doesn’t see a uniform ‘progression’ of science.

• If there is a uniform progression then only within a paradigm.

• He questions the rationality of science

The Copernican revolution

• Geocentrism, the Aristotelian worldview• Copernicus and the heliocentric worldview• Galileo Galilei and proof• As an effect of the Copernican revolution man

ceased to be the center of the universe

The inquisition forced Galileo to renounce his findings

Paul Feyerabend

The enemy of science

• Feyerabend thought Kuhn was killing creativity with normal science

• There is no such thing as rational scientific progress, not even within a paradigm.

Back to Galileo

• Against empirical evidence• Challenging observation rather than following it. • Galileo not only changed his worldview, but also

the way to measure it

If the earth moves why do things fall in a straight line?

Other observers tested Galileo’s telescope and did not see the same

His telescopic observations differ from normal observations

the sketches he made of the moon do not really resemble the moon at all.

Even worse, Galileo’s observations weren’t accurate

• Galileo and Copernicus worked contra-inductive.

• If we followed empirical research, then we would still be stuck with the Aristotelian view.

Inquisition and modern science

• Feyerabend compares modern science with the inquisition

• The inquisition only tried to defend the prevalent worldview

• He compares this with creationism

?

• Galileo succeeded despite, not thanks to rationality and induction.

• What really happened? • Creativity and social factors, public relations

so to say• What to do: go against the rules, whenever

possible.

Theoretical anarchism

Anything goes

Imre Lakatos

• Lakatos considered Kuhn’s idea’s as destructive

• He wanted to save the rationality of science• He proposes: research programs• He wanted back to Poppers rationality of

science

Research programs

• A research program is like a paradigm.• The difference is that their can be more than

one at the same time.• Every program has a hardcore and a protective

belt

Adjusting Popper

• Falsification forbids all ad hoc adjustment• Lakatos calls this naïve falsification• He suggest that the research programs should

get the time to develop• Rationality in the long run

Global Warming

Practical example: Global warming

• Is science being driven by social motives?• If so: isn’t that unscientific?• Is this a bad thing?• Is there room for alternatives?• Should governments act upon the global

warming hypothesis?• Give your own opinion on this debate