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Programa de Maestra en Gestin deTecnologas de Informacin y Comunicacin

(M-GTIC)

Nombre del Curso:

Filosofa de la Ciencia

(Philosophy of Science)Instructor:

Marvin Arias Olivas, PhD

E-mail: [email protected],[email protected]

Universidad Nacional de Ingeniera (UNI)

Managua, Nicaragua

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What is thisthing called

Science?Qu es

esa cosallamadaCiencia?


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Theories as Structures

Kuhn (1962): Science can be Normal orRevolutionary

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I have argued so far only that paradigms are constitutive ofscience. Now I wish to displaya sense in which they areconstitutive of nature as well .

(Thomas Kuhn 1922-1996)

Source: The Structu re of Scient i f icRevolu t ions (1962)


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One reason why there is seen to be a need to view theories

as structures stems from the history of science .

The notion can be further enhanced by reflecting on the factthat for a couple of centuries after Newton, physics wascarried out in the Newtonian framework, until thatframework was challenged by relativity and quantumtheory at the beginning of the last century.

One such alternative is the view that concepts acquire their

meaning by way of a definition.

Introduction: Theories as Structures

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Introduction: Theories as Structures

A key feature is the emphasis placed on the revolutionarycharacter of scientific progress,

A revolution involves the abandonment of one theoreticalstructure and its replacement by another, incompatible one.

The way a science progresses can be summarised by thefollowing open-ended scheme:

pre-sc ienc e - no rm al sc ience - c r i s i s - revolu t ion new n orm al sc ience - new c r i s i s

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Normal Science

Normal science' means research firmlybased upon one or more past scientificachievements, achievements that someparticular scientific community acknowledges

for a time as supplying the foundation for itsfurther practice.

Thomas S. Kuhn

The Structu re of Scient i f ic Revo lut io ns (1962).


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What is a Paradigm?

A scientific paradigm , in the most basic sense ofthe word, is a framework containing all of thecommonly accepted views about a subject, astructure of what direction research should take and

how it should be performed.

Thomas Kuhn suggested that a paradigm definesthe practices that define a scientific discipline atcertain point in time. He also postulated thatparadigms are discrete and culturally based.


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Normal Science


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What is a paradigm according to Kuhn?A paradigm is made up of the general theoreticalassumptions and laws and the techniques for their

application that the members of a particular scientificcommunity adopt.

Paradigms do not build on each other; a new

paradigm negates an older paradigm and rendersuseless all of the knowledge gained through researchconducted according to the earlier assumptions.

Paradigms and normal science


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A paradigm , therefore, determines not only a set of

beliefs about the world.

It also defines what counts as good science, andeven determines what counts as a scientific fact.

It is a conceptual framework that determines how theworld looks to those who have accepted it.

It defines not only the scientific outlook forpractitioners of a particular science, but also thescientific form of life.


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There are two aspects to the history of any science:

Norm al sc ience : science pursued within the constraints of aparticular paradigm, without questioning its principles. Thecharacteristic activity is puzzle solving,

Revolu t ion ary sc ience : a time of decreasing confidence inthe existing paradigm (because of the accumulation ofunsolved puzzles), and conflict with alternative paradigms.

This is like a political crisis, with uncertainty, and conflictamong many views, until a new order becomes establishedand a single paradigm takes a position of authority .

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The function of normal Science andRevolutions

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Normal science involves detailed attempts to articulate aparadigm with the aim of improving the math between it andnature.

It is research based upon past scientific achievementacknowledged by a scientific community as foundational forits further practice.

Examples of such achievements are Newton's Principia ,and Lavoisier's chemistry.


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Some philosophical claims arising from Kuhns view:

The conflict among paradigms cant be settled on any rationalmethodological grounds, because each paradigm contains itsown view of rational scientific methodology.

The conflict cant be resolved by an appeal to the facts, sinceeach paradigm contains a view of what counts as a fact, andwill determine how its adherents view the facts.

Different paradigms are in fact incommensurable, notcomparable by any neutral standard. Adherents of differentparadigms live in different worlds, and speak differentlanguages that are not inter-translatable.

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The merits of Kuhns account of Science


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A change of paradigm involves changes in the meanings ofbasic theoretical terms.The replacement of one paradigm by another cant be viewedas progressive on any objective grounds.

Since adherents of different paradigms define the questionsdifferently, and accept different standards for a good answer,the conflict between them has no neutral resolution.

A scientific revolution has to be regarded as a social and

psychological phenomenon rather than as a purelyintellectual one. For an individual scientist, the change inpoint of view is more like a religious conversion than arational process of comparing theories against the facts.

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Some historical claims arising from Kuhns view:

Scientists with different theoretical viewpoints generally fail tounderstand one another.

Competing paradigms appeal to different and conflictingsets of facts, and proceed by conflicting methods.

The arguments made in favor of one theory cannot be fullyunderstood by, or persuasive for , adherents of the other.

New paradigms introduce new theoretical terms, or changethe meanings of old ones, in ways that are incomprehensibleto anyone who doesnt already accept the new theory.

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A new paradigm doesnt explain more than its

predecessor. Even if it can explain things that the oldtheory couldnt, it will typically fail to explain many thingsthat the old theory could explain. ( This has been calledKuhn loss.

The history of science is not cumulative : new theoriescant incorporate the successes of older ones, becausethey have a completely different view of what counts as

success. The new theory redefines the old theory in itsown terms.

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Kuhns list of values for judging scientific theories:

Accuracy : degree of agreement with the available empiricaldata

Consis tency : freedom from logical contradictions

Simpl ic i ty : lack of unnecessary complication; unity Scope : Range of phenomena that fall within the theorysgrasp

Frui t fulness : Power to generate new principles, problems,solutions, predictions, etc.

Question: Does agreement on these values imply agreementon their application, their relative importance, etc?

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The Copernican Revolution

The Copernican Universe21


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What is objective knowledge and why is it relevant toKuhn's theory?

On the one hand, Kuhn is aware of the fact that a scientificrevolution extends over a considerable period of time

involving much theoretical and experimental work .

On the other hand, Kuhn's comparisons betweenparadigm change and gestalt switches or religiousconversions make immediate sense of the idea that thechange takes place "all at once".

Objective Knowledge


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What is objective knowledge and why is it relevant to

Kuhn's theory?Knowledge can be construed as objective by taking of theobjectives properties of statements, especially statements oftheoretical and observational claims.

The relevant to Kuhns theory is that not only such statementsthat are objective.

Experimental set-ups and procedures, methodological rules

and mathematical systems are objective too, in the sense thatthey are distinct from the kinds of things that reside inindividual minds. They can be confronted and can beexploited, modified and criticized by individuals .

Objective Knowledge


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Objective Knowledge


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Lakatoss research programs revisitedLakatos defines a research program as having a hard core

and a protective belt, and he specifies heuristic rules that tellus how to deal with the hard core and a protective belt. Wecan illustrate this by considering the Copernican theory.

The hard core of the Copernican theory is that the earth isspinning on its axis and that the planets revolve around thesun. The hard core of Copernican theory is different of theearth-centered Ptolemic theory it replaced.

For Ptolemy the central assumptions were that the earth wasstationary and the sun, moon and planets rotated around theearth.

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Lakatoss research programs revisitedThe protective belt of the Copernican theory is other

auxiliary, less crucial assumptions that are required in orderto the theory work. Copernicus assumed that the planetsmoved in epicycles.

This was needed by him to make specific predictions.However Kepler modified this protective belt assumption inthe Copernican theory by suggesting the planets moved inelliptical orbits around the sun.

Newton modified the protective belt further by suggestingthat the sun also moved a little.

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Lakatos:One program is superior to another insofar as it is amore successful predictor of novel phenomena.

A program is progressive to the extent that itmakes natural, as opposed to novel, predictions thatare confirmed, where "natural" stands opposed to

"contrived" or "ad hoc".theory.

Novel predictions

282012 M. Arias


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Lakatos shared Kuhn's concern with the history of

science.

Lakatos's methodology can be used tomeaningfully compare research programs.

In this connection, Lakatos came to make adistinction between the appraisal of researchprograms, which can only be done with historicalhindsight, and advice to scientists, which he deniedit was the purpose of his methodology to offer.

Testing the methodology againts history

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References What is this thing called Science?(Chapter 8 & 9).

An Introduction to the Philosophy of Science:Theory and Reality (Chapter 5 & 6).

Philosophy of Science: The Central IssuesMartin Curd and J. A. Cover (Chapter 2)

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