7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 1/21

What is a scientific

 theory?Dr. Ruth Conroy Dalton

1

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 2/21

A brief philosophical

introductionThe definit ion of research questions depends

above all on research method, and about  this there is a long standing history of 

philosophical debate 

2

2

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 3/21

Francis BaconBacon suggested that knowledge could be gained from the 

senses, but only byusing them throughcarefully constructedexperiments (since the senses err)

Essentially, Baconholds that data come first 

3

3

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 4/21

Rene Descartes

Only the most basic thoughts can be assumed

 to be true & a process of logical argument canconstruct knowledge from these alone 

Knowledge can be conducted in isolationfrom either prev ious

 thinkers or sense data 

4

4

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 5/21

Commonsense and the 

problem of inductionSince the sun rose  yesterday, and today

it wil l rise again tomorrow 

It seems that byobserving regularit ies

in the world we can‘induce’ generalprinciples or laws

5

5

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 6/21

David Hume 

What is the  justificat ion for the belief that the future 

 will be largely like the past?

Hume stated that there could be no basis inlogic for the assumption that past regularit ies will repeat 

6

6

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 7/21

Karl Popper Could ‘empiricalreasons’ ever be used to justify the 

assumption of truth or falsi ty of anystatement?

His answer was that 

although they couldnever just ify its truth they could prove itsfalsity

7

7

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 8/21

Popperian science 

Theory

Observation

Experiment 

8

8

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 9/21

Kuhn and paradigm

shiftsDominant sets of  ways we think about  things (paradigms)

Revolut ionary shiftsof paradigm

Causing the shifts are anomalous data andnew (younger) groupsof scient ists

9

9

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 10/21

Holmdel satelli te antenna, Bel l Labs N.J.

Penzias and Wilson10

10

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 11/21

Hacking and the 

creation of phenomena“Creation of phenomena which then becomes the 

subject of theory”

For Hacking the exper imentalist playsa key role, asimportant as the predict ions of the  theorist 

11

11

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 12/21

Creating phenomena

Theory

ObservationTransforming& Calculating

Representing

12

12

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 13/21

The social and the 

artificialExperimenting

Spotting regularit ies

Discovering mechanisms that have explanatorypower over the regularit ies

Generating classificat ions and names

13

13

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 14/21

Experiments

No fixed method

Follow hunches

Make it clear what the variables are and what isbeing kept constant 

Explore all the dimensions of a problem as far as

possible 

Develop methods for representing visually andmeasuring

14

14

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 15/21

Regularities

Those that act at the level of the individual

Those that act at the level of the group

Those that act at the level of a whole class of systems

15

15

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 16/21

Mechanisms

Mechanisms provide explanations for regularities

16

16

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 17/21

Classification and

namingClassificat ion is a procedure in which indiv idualitems are placed into groups based on quant itati ve informat ion on one or more characterist ics

inherent in the items (referred to as traits, variables, characters, etc)

One aspect of classification is the process of deciding what to observe (if two categories that behave 

differently are observed as a single class the result may hold no pattern)

17

17

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 18/21

The three principles of 

researchThe shortest model (or 

simplest theory) that accounts fully for the phenomena on hand ispreferable . This iscalled 'Occam's razor'

or the principle of parsimony

18

18

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 19/21

The three principles of 

researchThe shortest model (or simplest theory) that accounts ful ly for the phenomena on hand ispreferable . This is called 'Occam's razor' or the 

principle of parsimony

Wherever you come across an anomaly, place it at  the centre of the theoretical investigat ion

If there is more than one way of looking at things doboth

19

19

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 20/21

Paradoxes and

paradigms20

20

7/31/2019 Dalton Ruth Sd What is a Scientific Theory

http://slidepdf.com/reader/full/dalton-ruth-sd-what-is-a-scientific-theory 21/21

Questions and topics

Often research is a matter of followinghunches and intuit ions about interesting

 things to study and ways to study them...What is the question to which this topic isrelevant?

What is the question to which these methods are relevant?

21