1 introduktion till naturvetenskaplig tillvägagångssätt vid mälardalens högskola för...

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Introduktion till Naturvetenskaplig Tillvägagångssättvid Mälardalens Högskola

för Rudbeckianska Gymnasieelever

Gordana Dodig-Crnkovic

School of Innovation, Design and Engineering at Mälardalen University

19:e september 2008

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Videos

http://www.youtube.com/watch?v=XcbrKPj1V_U THC : Universe : Beyond Big Bang : 7/7 : Tour of Universe

http://www.youtube.com/watch?v=Vs5doooe2VY From Milky Way to Quarks

http://www.youtube.com/watch?v=RPumskk1dGk From Quarks to Outer Space

http://www.youtube.com/watch?v=H0CK9gapEqM&NR=1

End of the world?, the Large Hadron Collider ( LHC )

http://www.youtube.com/watch?v=nDOc1Z5eHSQ CERN Large Hadron Collider (LHC)

http://www.youtube.com/watch?v=W35SYkfdGtw Millennium Simulation: "The Largest Model of Our Universe"

http://www.youtube.com/watch?v=x6nwpcAcA0c The Universe - How Big Are You?

http://www.youtube.com/watch?v=dAzJy_DECyQ Cosmic Super Zoom

http://www.youtube.com/watch?v=U6QYDdgP9eg The Origin of Life – Abiogenesis

http://www.youtube.com/watch?v=OsDQ2jn2oAo Evolution of Life on Earth - Carl Sagan

http://www.youtube.com/watch?v=TOErr4xntHE Inside our Sun a deeper look

http://www.youtube.com/watch?v=fgg2tpUVbXQ&feature=related Hubble Deep Field: The Most Imp. Image Ever Taken (Redux)

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Red Thread: Critical Thinking

“Reserve your right to think,

for even to think wrongly

is better than not to think at all.”

Hypatia, natural philosopher and mathematician

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EyeMaurits Cornelis Escher

What Is Science?

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science from Latin scientia, scire to know;

1: a department of systematized knowledge as an object of study

2: knowledge or a system of knowledge covering general truths or the operation of general laws especially as obtained and tested through scientific method

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3: such knowledge or such a system of knowledge concerned with the physical world and its phenomena : natural science

4: a system or method reconciling practical ends with scientific laws <engineering is both a science and an art>

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To do science is to search for repeated patterns, not simply to accumulate facts.

Robert H. MacArthur

Religion is a culture of faith; science is a culture of doubt.

Richard Feynman

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What Sciences are there?Dewey Decimal Classification®

http://www.geocities.com/Athens/Troy/8866/15urls.html

000 - & Psychology200 - ReliComputers, Information & General Reference100 - Philosophy gion300 - Social sciences400 - Language500 - Science600 - Technology700 - Arts & Recreation800 - Literature900 - History & Geography

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3. Dewey Decimal Classification®

500 – Science510 Mathematics520 Astronomy530 Physics540 Chemistry550 Earth Sciences & Geology560 Fossils & Prehistoric Life570 Biology & Life Sciences580 Plants (Botany)590 Animals (Zoology)

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Culture(Religion, Art,

…)5

Natural Sciences(Physics,

Chemistry,Biology, …)

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Social Sciences(Economics, Sociology,

Anthropology, …)3

The Humanities(Philosophy, History,

Linguistics …)4

Logic

&

Mathematics

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Language Based SchemeClassical Sciences in their Cultural Context –

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Understanding what science is by understanding what scientists do

"Scientists are people of very dissimilar temperaments doing

different things in very different ways.

Among scientists are collectors, classifiers and compulsive

tidiers-up; many are detectives by temperament and many are

explorers; some are artists and others artisans.

There are poet-scientists and philosopher-scientists and even a

few mystics."

Peter Medawar, Pluto's Republic

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The narrow inductivist conception of scientific inquiry

1. All facts are observed and recorded.

2. All observed facts are analyzed, compared and classified, without hypotheses or postulates other than those necessarily involved in the logic of thought.

3. Generalizations inductively drawn as to the relations, classificatory or causal, between the facts.

4. Further research employs inferences from previously established generalizations.

6. Critique of Usual Naïve Image of Scientific Method (1)

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Socratic Method Scientific Method

1. Wonder. Pose a question(of the “What is X ?” form).

1. Wonder. Pose a question.(Formulate a problem).

2. Hypothesis. Suggest a plausible answer (a definition or definiens) from which some conceptually testable hypothetical propositions can be deduced.

2. Hypothesis. Suggest a plausible answer (a theory) from which some empirically testable hypothetical propositions can be deduced.

3. Elenchus ; “testing,” “refutation,” or “cross-examination.” Perform a thought experiment by imagining a case which conforms to the definiens but clearly fails to exemplify the definiendum, or vice versa. Such cases, if successful, are called counterexamples. If a counterexample is generated, return to step 2, otherwise go to step 4.

3. Testing. Construct and perform an experiment, which makes it possible to observe whether the consequences specified in one or more of those hypothetical propositions actually follow when the conditions specified in the same proposition(s) pertain. If the test fails, return to step 2, otherwise go to step 4.

4. Accept the hypothesis as provisionally true. Return to step 3 if you can conceive any other case which may show the answer to be defective.

4. Accept the hypothesis as provisionally true. Return to step 3 if there are predictable consequences of the theory which have not been experimentally confirmed.

5. Act accordingly. 5. Act accordingly.

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The Scientific Method

The hypotetico-deductive cycle

EXISTING THEORIESAND OBSERVATIONS

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SELECTION AMONG COMPETING THEORIES

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EXISTING THEORY CONFIRMED

(within a new context) or

NEW THEORY PUBLISHED

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Hypotesen måste

justeras

PREDICTIONS

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HYPOTHESIS

2

TESTS AND NEW OBSERVATIONS

4

Hypothesis must be

redefined

Hypothesis must be adjusted

The scientific-community cycle

Consistency achieved

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Formulating Research Questions and Hypotheses

Different approaches:

Intuition – (Educated) Guess

Analogy

Symmetry

Paradigm

Metaphor

and many more ..

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Criteria to Evaluate Theories

When there are several rivaling hypotheses number of criteria can be used for choosing a best theory.

Following can be evaluated:

– Theoretical scope– Heuristic value (heuristic: rule-of-thumb or argument

derived from experience)– Parsimony (simplicity, Ockham’s razor)– Esthetics– Etc.

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Criteria which Good Scientific Theory Shall Fulfill

– Logically consistent– Consistent with accepted facts – Testable– Consistent with related theories– Interpretable: explain and predict– Parsimonious– Pleasing to the mind (Esthetic, Beautiful)– Useful (Relevant/Applicable)

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What Is Knowledge?Plato´s Definition

Plato believed that we learn in this life by remembering knowledge originally acquired in a previous life, and that the soul already has knowledge, and we learn by recollecting what in fact the soul already knows.

Plato offers three analyses of knowledge, [dialogues Theaetetus 201 and Meno 98] all of which Socrates rejects.

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What Is Knowledge?Descartes´ Definition

"Intuitions provide the ultimate grounds for logical deductions. Ultimate first principles must be known through intuition while deduction logically derives conclusions from them.

These two methods [intuition and deduction] are the most certain routes to knowledge, and the mind should admit no others."

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What Is Knowledge?

– Propositional knowledge: knowledge that such-and-such is the case.

– Non-propositional knowledge (tacit knowledge): the knowing how to do something.

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Sources of Knowledge

– A Priori Knowledge (built in, developed by evolution and inheritance)

– Perception (“on-line input”, information acquisition)

– Reasoning (information processing)

– Testimony (network, communication)

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Knowledge and Objectivity: Observations

 Observations are always interpreted in the context of an a priori knowledge. (Kuhn, Popper)

“What a man sees depends both upon what he looks at and also upon what his previous visual-conceptual experience has taught him to see”.

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Knowledge and Objectivity Observations

– All observation is potentially ”contaminated”, whether by our theories, our worldview or our past experiences.

– It does not mean that science cannot ”objectively” [inter-subjectivity] choose from among rival theories on the basis of empirical testing.

– Although science cannot provide one with hundred percent certainty, yet it is the most, if not the only, objective mode of pursuing knowledge.

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Perception and “Direct Observation”

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Perception and “Direct Observation”

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Perception and “Direct Observation”

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Perception and “Direct Observation”

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Perception and “Direct Observation”

"Reality is merely an illusion, albeit a very persistent one." -

Einstein

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Perception and “Direct Observation”

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Perception and “Direct Observation”

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Perception and “Direct Observation”

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Perception and “Direct Observation”

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Perception and “Direct Observation”

Checker-shadow illusionhttp://web.mit.edu/persci/people/adelson/checkershadow_illusion.html

See even:http://persci.mit.edu/people/adelson/publications/gazzan.dir/gazzan.htm

Lightness Perception and Lightness Illusions

http://www.ihu.his.se/~christin/Vetenskapsteori/Vetenskapsteorikurser

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Truth and Reality

Noumenon,"Ding an sich" is distinguished from Phenomenon "Erscheinung", an observable event or physical manifestation, and the two words serve as interrelated technical terms in Kant's philosophy.

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TRUTH VS. PROVABILITY ACCORDING TO GÖDEL

After: Gödel, Escher, Bach - an Eternal Golden Braid by Douglas Hofstadter.