Scienceand

Scientific Worldviews?

B Gustafsson

Cemus August 31, 2007

Master Course, Leccture 1

Definition: Wikipedia (Karl Popper)

• Science (from the Latin scientia , ' knowledge ') is a system of acquiring

knowledge based on the scientific method , as well as the organized body of knowledge gained through such research .

Scientific method

• Scientific method is a body of techniques for investigating phenomena and acquiring new knowledge , as well as for correcting and integrating previous knowledge. It is based on

• gathering observable ,empirical and measurable evidence subject to specific principles of reasoning ,

• the collection of data through observation and experimentation , and

• the formulation and testing of hypotheses.

- gathering observable ,empirical and measurable evidence…

• Both unconditioned observations (prior to any theory) and observations of results of designed experiments

• Information must be reliable, i.e. repeatable (and reproduceable) as well as relevant to the inquiry

• So, what does this exclude?

• We will get a description we (in principle) can share with everybody.

• Is that all that is ”true knowledge”?

Control

• Actively and fairly sampling the range of possible occurences -- not only passive acceptance of data that happen to be available to balance bias

• Identification and study of possible errors• Archiving, sharing of data, publishing,

double checks by colleagues • Testing by applying (technology)

Hypotheses and theories

• Theories may bind hypotheses together• Formulation of hypotheses -- ”all means allowed”• Science: testing of accuracy of hypotheses• Structuring of theories: if possible - logical, with little or no contradictions: they

should be consistent - range of validity should be explored and defined

Theories do NOT replace hypotheses!

Rules of thumb for making hypotheses

• Ockham’s razor

• You must be able to tell how

one could refute it (Popper)

• How about the converse?

• Search for the most probable

hypothesis to explain the

observed data (”abduction”)

Testing teories

• Internal consistency

• Experimental verification of PREDICTIONS

Power of a theory -- predictive power

• UTILITY TEST!

• Ability to stimulate work -- and alternative theories!

How to find causes (explantions)

• Time-order relation (A -> B)

• Co-variation of A and B

• Elimination of other possibilities

• Theoretical consistency (?)

Positivism (August Comte): The only authentic knowledge is that

derived by the scientific method

cf Hermeneutics:

Theories of the interpretation and understanding of texts

and also of human behaviour

a more individually centered perspective

Reductionism:

Enteties on one kind are reduceable to enteties of another, e.g.

• Mental events to chemical events• Social processes to actions and relationships

between individuals• Biological organisms to physical systems• Planets to elementary particles

Critique against the Scientific Method

Thomas Samuel Kuhn (”The Structure of Scientific Revolutions”, 1962): actual methods used

differ dramatically!Paul Feyerabend (”Against method”, 1975): Scientific

progress is NOT the result of applying any particular method. ”Anything goes” Michael Polanyi (”Personal knowledge”, 1958):

Scientists must follow personal passions in appraising facts and determining relevance

Postmodern critiqueJean-Francois Lyotard (La Condition Postmoderne: Rapport sur le savoir, 1979):”Metanarratives of progress” -- positivist science, Marxism,

structuralism, … are defunct as methods of progress. They are just ”stories” told in order to legitimise various versions of ”the truth”. ”Whose truth” is the question to ask! Is modern science just ”customized for the capitalist market?”

Relativism; may indirectly legitimise other approaches such as ”Ideological-religious science”.

”Science war” still going on. ”Social construct of what?”

What is characteristic of the scientific worldview(s)?

• Common (if you follow the rules). Whose rules then?

What is characteristic of the scientific worldview(s)?

• Common

• => Simplified, reductionistic, logical, mechanistic

What is characteristic of the scientific worldview(s)?

• Common

• => Simplified, reductionistic, logical, mechanistic

• Useful (for whom?)

What is characteristic of the scientific worldview(s)?

• Common

• => Simplified, reductionistic, logical, mechanistic

• Useful

• Non-trivial (and even unexpected!)

What is characteristic of the scientific worldview(s)?

• Common • => Simplified, reductionistic, logical, mechanistic• Useful • Non-trivial• Beautiful

What is characteristic of the scientific worldview(s)?

• Common (if you follow the rules).• => Simplified, reductionistic, logical, mechanistic• Useful • Non-trivial• Beautiful• Consistent (”more than we had any reason to

expect”)

What is characteristic of the scientific world view(s)?

• Common • => Simplified, reductionistic, logical, mechanistic• Useful • Non-trivial• Beautiful• Consistent• Bizarre

One example:

•Black holes”The most delightful objects of Nature”Subrahmanyan Chandrasekhar

Predicted by General Relativity in 1916