The Structure of Scientific Revolutions Part II

1. The Structure of Scientific Revolutions Part II Presented by: Joanna (Yuewei) Zhou for ICS 280 WQ 2004 Research Methodology for Software

2. Part I, Paradigms of Science Pre-Science Grow out of everyday intuition Evolve into its own delicate form of concepts and methodologies The established paradigm determines: How scientists do research How they determine research-worthy problems How they evaluate research results How they teach new members and maintain the consensus Paradigm Change Discovery & Invention: novelty of facts and theories New anomaly will force the paradigm to shift to explain them

3. Invention of New Theory Leads to Paradigm Change In the beginning, several alternative theories After competition�dominant explanation framework Once a theory is entrenched, change will be difficult Established theory will be resilient to explain new facts More general, inclusive, but without significantly deviating the original framework When there is discrepancy b/w the theory and the facts, new theory is needed An established theory seldom yields on the first attack Flexible and adaptive to suit new facts The change in paradigm could take a long time span

4. Response to Crisis Crisis: Discrepancy b/w the established paradigm and unexplainable parts Necessary part of scientific process: sounds negative, positive side Essential tension Normal research activity: an effort to resolve the tension b/w the puzzle and the theory Scientists� response to Crisis They will try to patch the current theory: modify, extend, adapt Eventually, they will invent a new theory They can quit, discrediting of their reputation A crisis is much more than a simple anomaly Eminent authority The subject of the whole discipline Philosophical debate, loosing the basic limits

5. Resolution of Crisis Three ways of resolution Return to normal Set aside A new paradigm Invalidate old paradigm and take its place Reconstruction of the field from new fundamentals Introduce new concepts, rules, and applications Emergence of paradigm: sudden; young folks Scientific Revolution: establishment of a new paradigm Extraordinary Science (vs. normal science) Go to next�

6. Nature and Necessity of Scientific Revolution Scientific Revolution Like political revolution A change to be called a revolution Fundamentally incompatible with the existing paradigm Two sides Not share the same basic logic Different in what is research-worthy, how things can be explained Only be resolved by a dramatic change Kuhn�s point: Scientific revolution is not cumulative Demand the rejection of the old paradigm Destruct the old beliefs of the nature

7. Revolution as Change of World View World View Change Reasons for Change Genius Different interpretation? No Human perception change? No Different definitional convention? No Failure of old paradigm, guidance and better results

8. Revolution: Is it invisible? Scientific revolution Dramatic nature, however, might look invisible Textbook Authoritative source of scientific knowledge Problems with textbook Educational purpose Not convey the revolutionary nature of the paradigm change Little historical context Piecemeal accumulation Scientists� own vision Reconstruction: cumulative or linear, NOT the real case Misconstruction: inaccurate

9. Conversion to the New Paradigm Conversions occur as generations change How fast does the revolution happen? Reasons for conversion Faith on application to future problems When not agree on the past achievements, see which is better in dealing with unexpected or unexplored problems Aesthetic reason Neater, more suitable, simpler, or more elegant Gradual conversion

10. Progress through Revolutions Relationship b/w progress and science A discipline establishes itself as science when its accomplishments is beyond argument Progress is the nature of science Visible progress When paradigm in normal science can assure success and make it obvious A paradigm establishes a community Share common beliefs on questions, methods, and evaluation of solutions Solve problems of the nature Satisfy both individual scientist and community No external judgment; shared goal, belief and principle Paradigm change as progress because allow new solution

11. Summary Paradigm Defined as the dominant establishment for shared concepts, methods, and values for solving scientific problems Crisis When current paradigms cannot explain all existing data Resolved by a new paradigm New paradigm takes over the old one Revolutionary process is gradual Paradigm shift is how science progresses and advances

12. Discussion Questions How often is the revolution? Software crisis: more chronic? Can we apply the crisis/paradigm shift in SW? What was the old paradigm (if we can)? What is the new? What is the crisis that brings the new paradigm into being (if there is any)? How does software engineering, as a scientific discipline, evolve (if we cannot determine a paradigm shift at least in Kuhn�s sense)? Does it do so accumulatively? Is it too early to say? Community How does a community come into existence? When two communities attack the same problem, how can they talk with each other in a manner that is understandable and beneficial to both participants? Result of human society; the problems of nature or its computerization does not have this concept, neither does it need