A paradigm shift, a concept identified by
the American physicist and philosopher Thomas
Kuhn, is a fundamental change in the basic
concepts and experimental practices of a scientific
discipline. Kuhn contrasts paradigm shifts,
which characterize a scientific revolution,
to the activity of normal science, which he
describes as scientific work done within a
prevailing framework (or paradigm). In this
context, the word "paradigm" is used in its
original Greek meaning, as "example".
The nature of scientific revolutions has been
studied by modern philosophy since Immanuel
Kant used the phrase in the preface to the
second edition of his Critique of Pure Reason
(1787). Kant used the phrase "revolution of
the way of thinking" (Revolution der Denkart)
to refer to Greek mathematics and Newtonian
physics. In the 20th century, new developments
in the basic concepts of mathematics, physics,
and biology revitalized interest in the question
among scholars.
Kuhn presented his notion of a paradigm shift
in his influential book The Structure of Scientific
Revolutions (1962). As one commentator summarizes:
Kuhn acknowledges having used the term "paradigm"
in two different meanings. In the first one,
"paradigm" designates what the members of
a certain scientific community have in common,
that is to say, the whole of techniques, patents
and values shared by the members of the community.
In the second sense, the paradigm is a single
element of a whole, say for instance Newton’s
Principia, which, acting as a common model
or an example... stands for the explicit rules
and thus defines a coherent tradition of investigation.
Thus the question is for Kuhn to investigate
by means of the paradigm what makes possible
the constitution of what he calls "normal
science". That is to say, the science which
can decide if a certain problem will be considered
scientific or not. Normal science does not
mean at all a science guided by a coherent
system of rules, on the contrary, the rules
can be derived from the paradigms, but the
paradigms can guide the investigation also
in the absence of rules. This is precisely
the second meaning of the term "paradigm",
which Kuhn considered the most new and profound,
though it is in truth the oldest.
Even though Kuhn restricted the use of the
term to the natural sciences, the concept
of a paradigm shift has also been used in
numerous non-scientific contexts to describe
a profound change in a fundamental model or
perception of events.
== Kuhnian paradigm shifts ==
An epistemological paradigm shift was called
a "scientific revolution" by epistemologist
and historian of science Thomas Kuhn in his
book The Structure of Scientific Revolutions.
A scientific revolution occurs, according
to Kuhn, when scientists encounter anomalies
that cannot be explained by the universally
accepted paradigm within which scientific
progress has thereto been made. The paradigm,
in Kuhn's view, is not simply the current
theory, but the entire worldview in which
it exists, and all of the implications which
come with it. This is based on features of
landscape of knowledge that scientists can
identify around them.
There are anomalies for all paradigms, Kuhn
maintained, that are brushed away as acceptable
levels of error, or simply ignored and not
dealt with (a principal argument Kuhn uses
to reject Karl Popper's model of falsifiability
as the key force involved in scientific change).
Rather, according to Kuhn, anomalies have
various levels of significance to the practitioners
of science at the time. To put it in the context
of early 20th century physics, some scientists
found the problems with calculating Mercury's
perihelion more troubling than the Michelson-Morley
experiment results, and some the other way
around. Kuhn's model of scientific change
differs here, and in many places, from that
of the logical positivists in that it puts
an enhanced emphasis on the individual humans
involved as scientists, rather than abstracting
science into a purely logical or philosophical
venture.
When enough significant anomalies have accrued
against a current paradigm, the scientific
discipline is thrown into a state of crisis,
according to Kuhn. During this crisis, new
ideas, perhaps ones previously discarded,
are tried. Eventually a new paradigm is formed,
which gains its own new followers, and an
intellectual "battle" takes place between
the followers of the new paradigm and the
hold-outs of the old paradigm. Again, for
early 20th century physics, the transition
between the Maxwellian electromagnetic worldview
and the Einsteinian relativistic worldview
was neither instantaneous nor calm, and instead
involved a protracted set of "attacks," both
with empirical data as well as rhetorical
or philosophical arguments, by both sides,
with the Einsteinian theory winning out in
the long run. Again, the weighing of evidence
and importance of new data was fit through
the human sieve: some scientists found the
simplicity of Einstein's equations to be most
compelling, while some found them more complicated
than the notion of Maxwell's aether which
they banished. Some found Arthur Eddington's
photographs of light bending around the sun
to be compelling, while some questioned their
accuracy and meaning. Sometimes the convincing
force is just time itself and the human toll
it takes, Kuhn said, using a quote from Max
Planck: "a new scientific truth does not triumph
by convincing its opponents and making them
see the light, but rather because its opponents
eventually die, and a new generation grows
up that is familiar with it."After a given
discipline has changed from one paradigm to
another, this is called, in Kuhn's terminology,
a scientific revolution or a paradigm shift.
It is often this final conclusion, the result
of the long process, that is meant when the
term paradigm shift is used colloquially:
simply the (often radical) change of worldview,
without reference to the specificities of
Kuhn's historical argument.
In a 2015 retrospective on Kuhn, the philosopher
Martin Cohen describes the notion of the paradigm
shift as a kind of intellectual virus – spreading
from hard science to social science and on
to the arts and even everyday political rhetoric
today. Cohen claims that Thomas Kuhn himself
had only a very hazy idea of what it might
mean and, in line with the American philosopher
of science, Paul Feyerabend, accuses Kuhn
of retreating from the more radical implications
of his theory, which are that scientific facts
are never really more than opinions, whose
popularity is transitory and far from conclusive.
== Science and paradigm shift ==
A common misinterpretation of paradigms is
the belief that the discovery of paradigm
shifts and the dynamic nature of science (with
its many opportunities for subjective judgments
by scientists) are a case for relativism:
the view that all kinds of belief systems
are equal. Kuhn vehemently denies this interpretation
and states that when a scientific paradigm
is replaced by a new one, albeit through a
complex social process, the new one is always
better, not just different.
These claims of relativism are, however, tied
to another claim that Kuhn does at least somewhat
endorse: that the language and theories of
different paradigms cannot be translated into
one another or rationally evaluated against
one another—that they are incommensurable.
This gave rise to much talk of different peoples
and cultures having radically different worldviews
or conceptual schemes—so different that
whether or not one was better, they could
not be understood by one another. However,
the philosopher Donald Davidson published
a highly regarded essay in 1974, "On the Very
Idea of a Conceptual Scheme" (Proceedings
and Addresses of the American Philosophical
Association, Vol. 47, (1973–1974), pp. 5–20)
arguing that the notion that any languages
or theories could be incommensurable with
one another was itself incoherent. If this
is correct, Kuhn's claims must be taken in
a weaker sense than they often are. Furthermore,
the hold of the Kuhnian analysis on social
science has long been tenuous with the wide
application of multi-paradigmatic approaches
in order to understand complex human behaviour
(see for example John Hassard, Sociology and
Organization Theory: Positivism, Paradigm
and Postmodernity. Cambridge University Press,
1993, ISBN 0521350344.)
Paradigm shifts tend to be most dramatic in
sciences that appear to be stable and mature,
as in physics at the end of the 19th century.
At that time, physics seemed to be a discipline
filling in the last few details of a largely
worked-out system. In 1900, Lord Kelvin famously
told an assemblage of physicists at the British
Association for the Advancement of Science,
"There is nothing new to be discovered in
physics now. All that remains is more and
more precise measurement."[veracity of this
quote challenged in Lord Kelvin article] Five
years later, Albert Einstein published his
paper on special relativity, which challenged
the very simple set of rules laid down by
Newtonian mechanics, which had been used to
describe force and motion for over two hundred
years.
In The Structure of Scientific Revolutions,
Kuhn wrote, "Successive transition from one
paradigm to another via revolution is the
usual developmental pattern of mature science."
(p. 12) Kuhn's idea was itself revolutionary
in its time, as it caused a major change in
the way that academics talk about science.
Thus, it could be argued that it caused or
was itself part of a "paradigm shift" in the
history and sociology of science. However,
Kuhn would not recognise such a paradigm shift.
In the social sciences, people can still use
earlier ideas to discuss the history of science.
Philosophers and historians of science, including
Kuhn himself, ultimately accepted a modified
version of Kuhn's model, which synthesizes
his original view with the gradualist model
that preceded it.
== Examples of paradigm shifts ==
=== Natural sciences ===
Some of the "classical cases" of Kuhnian paradigm
shifts in science are:
1543 – The transition in cosmology from
a Ptolemaic cosmology to a Copernican one.
1543 – The acceptance of the work of Andreas
Vesalius, whose work De humani corporis fabrica
corrected the numerous errors in the previously-held
system created by Galen.
1687 – The transition in mechanics from
Aristotelian mechanics to classical mechanics.
1783 – The acceptance of Lavoisier's theory
of chemical reactions and combustion in place
of phlogiston theory, known as the chemical
revolution.
The transition in optics from geometrical
optics to physical optics with Augustin-Jean
Fresnel's wave theory.
1826 – The discovery of hyperbolic geometry.
1859 – The revolution in evolution from
goal-directed change to Charles Darwin's natural
selection.
1880 - The germ theory of disease began overtaking
Galen's miasma theory.
1905 – The development of quantum mechanics,
which replaced classical mechanics at microscopic
scales.
1887 to 1905 – The transition from the luminiferous
aether present in space to electromagnetic
radiation in spacetime.
1919 – The transition between the worldview
of Newtonian gravity and the Einsteinian General
Relativity.
=== Social sciences ===
In Kuhn's view, the existence of a single
reigning paradigm is characteristic of the
natural sciences, while philosophy and much
of social science were characterized by a
"tradition of claims, counterclaims, and debates
over fundamentals." Others have applied Kuhn's
concept of paradigm shift to the social sciences.
The movement known as the cognitive revolution
moved away from behaviourist approaches to
psychological study and the acceptance of
cognition as central to studying human behaviour.
The Keynesian revolution is typically viewed
as a major shift in macroeconomics. According
to John Kenneth Galbraith, Say's Law dominated
economic thought prior to Keynes for over
a century, and the shift to Keynesianism was
difficult. Economists who contradicted the
law, which implied that underemployment and
underinvestment (coupled with oversaving)
were virtually impossible, risked losing their
careers. In his magnum opus, Keynes cited
one of his predecessors, John A. Hobson, who
was repeatedly denied positions at universities
for his heretical theory.
Later, the movement for monetarism over Keynesianism
marked a second divisive shift. Monetarists
held that fiscal policy was not effective
for stabilizing inflation, that it was solely
a monetary phenomenon, in contrast to the
Keynesian view of the time was that both fiscal
and monetary policy were important. Keynesians
later adopted much of the monetarists' view
of the quantity theory of money and shifting
Phillips curve, theories they initially rejected.
First proposed by Ferdinand de Saussure in
1879, the laryngeal theory in Indo-European
linguistics postulated the existence of "laryngeal"
consonants in the Proto-Indo-European language
(PIE), a theory that was confirmed by the
discovery of the Hittite language in the early
20th century. The theory has since been accepted
by the vast majority of linguists, paving
the way for the internal reconstruction of
the syntax and grammatical rules of PIE and
is considered one of the most significant
developments in linguistics since the initial
discovery of the Indo-European language family.
=== Applied sciences ===
More recently, paradigm shifts are also recognisable
in applied sciences:
In medicine, the transition from "clinical
judgment" to evidence-based medicine
In software engineering, the transition from
the Rational Paradigm to the Empirical Paradigm
== 
Marketing ==
In the later part of the 1990s, 'paradigm
shift' emerged as a buzzword, popularized
as marketing speak and appearing more frequently
in print and publication. In his book Mind
The Gaffe, author Larry Trask advises readers
to refrain from using it, and to use caution
when reading anything that contains the phrase.
It is referred to in several articles and
books as abused and overused to the point
of becoming meaningless.
== Other uses ==
The term "paradigm shift" has found uses in
other contexts, representing the notion of
a major change in a certain thought-pattern—a
radical change in personal beliefs, complex
systems or organizations, replacing the former
way of thinking or organizing with a radically
different way of thinking or organizing:
M. L. Handa, a professor of sociology in education
at O.I.S.E. University of Toronto, Canada,
developed the concept of a paradigm within
the context of social sciences. He defines
what he means by "paradigm" and introduces
the idea of a "social paradigm". In addition,
he identifies the basic component of any social
paradigm. Like Kuhn, he addresses the issue
of changing paradigms, the process popularly
known as "paradigm shift". In this respect,
he focuses on the social circumstances which
precipitate such a shift. Relatedly, he addresses
how that shift affects social institutions,
including the institution of education.
The concept has been developed for technology
and economics in the identification of new
techno-economic paradigms as changes in technological
systems that have a major influence on the
behaviour of the entire economy (Carlota Perez;
earlier work only on technological paradigms
by Giovanni Dosi). This concept is linked
to Joseph Schumpeter's idea of creative destruction.
Examples include the move to mass production
and the introduction of microelectronics.
Two photographs of the Earth from space, "Earthrise"
(1968) and "The Blue Marble" (1972), are thought
to have helped to usher in the environmentalist
movement which gained great prominence in
the years immediately following distribution
of those images.
Hans Küng applies Thomas Kuhn's theory of
paradigm change to the entire history of Christian
thought and theology. He identifies six historical
"macromodels": 1) the apocalyptic paradigm
of primitive Christianity, 2) the Hellenistic
paradigm of the patristic period, 3) the medieval
Roman Catholic paradigm, 4) the Protestant
(Reformation) paradigm, 5) the modern Enlightenment
paradigm, and 6) the emerging ecumenical paradigm.
He also discusses five analogies between natural
science and theology in relation to paradigm
shifts. Küng addresses paradigm change in
his books, Paradigm Change in Theology and
Theology for the Third Millennium: An Ecumenical
View.
== See also ==
== References ==
=== Citations ===
=== Sources ===
Kuhn, Thomas (1970). The Structure of Scientific
Revolutions (2nd, enlarged ed.). University
of Chicago Press. ISBN 978-0-226-45804-5.
== External links ==
MIT 6.933J – The Structure of Engineering
Revolutions. From MIT OpenCourseWare, course
materials (graduate level) for a course on
the history of technology through a Kuhnian
lens.
""Scientific Change"". Internet Encyclopedia
of Philosophy.
