Making Theoretical Progress

Deduction vs. Induction

Deductive (top down) reasoning:

More narrow

Concerned with hypothesis testing

Inductive (bottom up) reasoning:

More open-ended

More exploratory

Every swan I see is white so all swans are white (bottom up) --> specific observations --> patterns --> develop theory

All swans are white so the next swan I see will be white -->
Theory --> hypothesis --> observation --> confirmation

Problems with Verification

20th Century Approach: What is Science?

Critical Questions:

  • What's unique about science?
  • What is science? What is non-science?
  • Can the scientific method be identified & applied to other fields of knowledge?

A group of philosophers discussed these questions --> logical positivism

What are the demarcation criteria that define science?

The Vienna Circle: Logical Positivism - Verification, observation, induction --> demarcation of science (proceeds through cycle)

Translating individual observations into general conclusions --> demarcation

A statement was only regarded as scientific if it could be verifed as true or false through objective observation

Falsification (Popper)

Verification is logically impossible

Induction Problem: Just because you make a lot of observations coming to the same conclusions, it doesn't mean this will always happen

Unobservable facts: Overtime, unobservable things may become observable e.g looking at the atom

Observations may be wrong: e.g. illusion of the lines that look different but are the same

Observations not objective: Using verification for the demarcation of science is problematic - logical positivists were called naive & called into question

Falsification instead of Verification

Austrian born scholar

Member of the Vienna Circle

Initial interest in psychology - 'I can't account for the essence of scientific progress

Popper

Falsification instead of verification

Science constantly questions its explanations

Considerations the differences between physics & Freudian Psychoanalysis

Falsifiable or not?

Hypothetico-Deductive Method

Degrees of F.

Criteria for Choosing Theories

Kuhn's Theory of Scientific Progress

  1. It never rains on Wednesday - yes
  2. Kennedy died from a bullet - yes
  3. If he'd lived, Kennedy would have ended the Vietnam War - no

Physics: Progress through finding weaknesses of theories

Psychoanalysis: Progress through finding corroborating evidence

Falsification differentiates science from pseudo science

Verification is impossible to prove in an inductive conclusion - easy to disprove

Observation --> Interpretation --> Hypothesis -- > Test

Based on inductive reasoning

Make sure scientific explanations are scientifically grounded

The more falsifiable a theory, the higher it's scientific status

Example - Louis Pasteur - why do wine, beer & milk sour?
Due to organisms in the air --> test

Provide evidence for theory using filter to prevent organisms entering

E.g. 1. Wine sours from organisms

  1. Wine sours from bacteria in the air
  1. = more falsifiable because it has more specificity --> more specific = more prone to falsification = higher scientific status

Scope

A good theory is one that makes wide ranging claims with a wide scope

Example: 1. Mars moves in an eclipse around the sun

  1. All planets move around the sun

Precision

  1. has a higher status as it tells you what the first said and more

The more precise a theory the more falsifiable it is

Example: 1. Planets move in ellipses around the sun

  1. Planets move in closed loops around the sun

Oval orbits would falsify 1st not 2nd
ANY orbit falsifies 1st AND 2nd

Operational Definition - Describes exactly what the variables are & how they'll be measured --> e.g. are toddlers happier in warm or cold weather? Operationally define by testing how many smiles in each

Parsimony

Among competing theories, the one that makes the fewest assumptions should be favoured. Occam's Razor --> simple theories prefered

Example: Event - it's raining & I saw a bright flash

  1. Lightening
  2. Someone is taking a picture of me
  1. Is simple - so it's preferred

Increasing Falsifiability

The more falsifiable the theory the better. More content, more informative

A replacement theory should be more falsifiable than what it replaced

Example:

  • All bread nourishes
  • All bread, except a particular batch nourishes
  • All bread nourishes except that batch due to a fungus

3 Is best --> modified theory is not ad-hoc

Fruitfulness

Has the theory --> new empirical discoveries --> scientific progress

Example: Theory = Bats have weak eyes but can see
Test = Blindfold bats & release

American psychiatrist - Science is a social activity

Scientific paradigm --> Set of common views of what the discipline is about & how problems should be investigated

Introduced the term scientific paradigm - any scientific achievements were part of a paradigm --> stages

Pre-science --> normal science --> crisis --> revolution --> new normal science --> new crisis

A paradigm determines:

  • What is to be observed & scrutinised
  • What kinds of questions should be asked? etc.

Kuhn- Structure of Scientific Revolution

Each discipline starts with facts to explain small scale phenomena

Researchers share paradigms - attempts made to falsify the theory - modifications can be made

Revolution - confidence in paradigm decreases, crisis, scientific revolution & paradigm shift

Does a revolution really mean progress or does it just mean change?

Puzzle solving NOT problem solving

Kuhn:

  • Normal science = important
  • Scientists should criticise occasionally
  • Conformity & puzzle solving

Popper:

  • Critical is best
  • Criticism & non-conformity are essential

Problems

Too vague

How long should scientists stick with a theory in the face of trouble spots

Why would working with a theory for a long time improve the chance of identifying limitations

Both Popper vs. Kuhn are opposite extremists on the issues

Popper --> all scientists should follow same critical procedures

Kuhn --> should puzzle solve

Middle Ground - Constant coupling of ideas to observations by using verification & falsification is a guarantee that the ideas will not be completely in contradiction with the reality as it can be observed = Rule of Thumb - look at converging evidence