Background

Karl Raimund Popper was born on 28 July 1902 in Vienna, which at that time could make some claim to be the cultural epicenter of the western world. His father Simon Siegmund Carl Popper was a lawyer from Bohemia and a doctor of law at the Vienna University while his mother Jenny Schiff was of Silesian and Hungarian descent. His parents, who were of Jewish origin, brought him up in an atmosphere which he was later to describe as ‘decidedly bookish.’ His father was a lawyer by profession, but he also took a keen interest in the classics and in philosophy and communicated to his son an interest in social and political issues which he was to never lose. His mother inculcated in him such a passion for music that for a time he seriously contemplated taking it up as a career, and indeed he initially chose the history of music as a second subject for his doctoral examination. Subsequently, his love for music became one of the inspirational forces in the development of his thought, and manifested itself in his highly original interpretation of the relationship between dogmatic and critical thinking, in his account of the distinction between objectivity and subjectivity, and, most importantly, in the growth of his hostility towards all forms of historicism, including historicist ideas about the nature of the ‘progressive’ in music.

Education

The young Karl Popper attended the Wiedner Gymnasium, where he was unhappy with the standards of the teaching, and, after an illness which kept him at home for a number of months, he left to attend the University of Vienna in 1918. However, he did not formally enroll at the university by taking the matriculation examination for another four years. 1919 was in many respects the most important formative year of his intellectual life. In that year he became heavily involved in left-wing politics, joined the Association of Socialist School Students, and became for a time a Marxist. However, he was quickly disillusioned with the doctrinaire character of the latter and soon abandoned it entirely. He also discovered the psychoanalytic theory of Freud and the individual psychology theory Adler (he served briefly as a voluntary social worker with deprived children in one of the latter’s clinics in the 1920s), and listened entranced to a lecture which Einstein gave in Vienna on relativity theory. The dominance of the critical spirit in Einstein, and what he considered its total absence in Marx, Freud, and Adler, struck Popper as being of fundamental importance: the pioneers of psychoanalysis, he came to think, couched their theories in terms which made them amenable only to confirmation, while Einstein’s theory, crucially, had testable implications which, if false, would have falsified the theory itself.

Popper trained as a cabinetmaker, obtained a primary school teaching diploma in 1925, and qualified to teach mathematics and physics in a secondary school in 1929. He undertook a doctoral program with the department of psychology at the University of Vienna under the supervision of Karl Bühler, who, with Otto Külpe, was one of the founder members of the Würzburg school of experimental psychology. Popper’s project was initially designed as a psychological investigation of human memory, on which he had conducted initial research. However, the subject matter of a planned introductory chapter on methodology assumed a position of increasing pre-eminence and this resonated with Bühler, who, as a distinguished Kantian scholar, a professor of philosophy as well as psychology, had famously addressed the issue of the contemporary ‘crisis in psychology.’ This ‘crisis,’ for Bühler, related to the question of the unity of psychology and had been generated by the proliferation of then competing paradigms within psychology which had undermined the hitherto dominant associationist one and problematized the question of method. Accordingly, under Bühler’s direction, Popper switched his topic to the methodological problem of cognitive psychology and received his doctorate in 1928 for his dissertation “Die Methodenfrage der Denkpsychologie."

Career

In 1937 Karl Popper took up a position teaching philosophy at the University of Canterbury in New Zealand, where he was to remain for the duration of the Second World War, though he had a rather tense relationship with his head of department. Additionally, his wife had difficulty adapting to life away from her native Vienna and homesickness made her increasingly unhappy; this was exacerbated by the sheer relentlessness of Popper’s personal work ethic, which they both found exhausting.

The annexation of Austria in 1938 became the catalyst which prompted Popper to refocus his writings on social and political philosophy, and he published The Open Society and Its Enemies, his critique of totalitarianism, in 1945. In 1946, he moved to England to teach at the London School of Economics and became a professor of logic and scientific method at the University of London in 1949. From this point on his reputation and stature as a philosopher of science and social thinker grew enormously, and he continued to write prolifically - a number of his works, particularly The Logic of Scientific Discovery (1959), are now widely seen as pioneering classics in the field. However, he combined a combative personality with a zeal for self-aggrandizement that did little to endear him to professional colleagues at a personal level. He was ill-at-ease in the philosophical milieu of post-war Britain which was, as he saw it, fixated with trivial linguistic concerns dictated by Wittgenstein, whom he considered to be his nemesis. Popper was a somewhat paradoxical man, whose theoretic commitment to the primacy of rational criticism was counterpointed by hostility towards anything that amounted to less than total acceptance of his own thought, and in Britain - as had been the case in Vienna - he became increasingly an isolated figure, though his ideas continued to inspire admiration.

In later years Popper came under philosophical criticism for his prescriptive approach to science and his emphasis on the logic of falsification. This was superseded in the eyes of many by the socio-historical approach taken by Thomas Kuhn in The Structure of Scientific Revolutions (1962), who - in arguing for the incommensurability of rival scientific paradigms - reintroduced the idea that change in science is essentially dialectical and is dependent upon the establishment of consensus within communities of researchers.

Popper was knighted in 1965, and retired from the University of London in 1969, though he remained active as a writer, broadcaster, and lecturer until his death in 1994.

Achievements

• Karl Popper changed the way of scientific thinking. Scientific theories were thought to be tested by a process of verification. Popper showed they could only be tested by falsification. If a theory can be falsified, he said, it counts as science. Otherwise, it is pseudoscience or simply outside the limits of science. His hypothetico-deductive model of the scientific method has largely replaced the older deductive and inductive models. He was awarded prizes and honors throughout the world, including the Austrian Grand Decoration of Honour in Gold, the Lippincott Award of the American Political Science Association, and the Sonning Prize for merit in work which had furthered European civilization.

Works

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  • The Two Fundamental Problems of the Theory of Knowledge

    (The two fundamental problems of knowledge that lie at the...)

    1933
  • In Search of a Better World: Lectures and Essays from Thirty Years

    ("I want to begin by declaring that I regard scientific kn...)

    1984
  • The Open Society and Its Enemies

    (A landmark defense of democracy that has been hailed as o...)

    1945
  • The Logic of Scientific Discovery

    (This book by one of the world's foremost philosophers of ...)

    1934
  • The World of Parmenides: Essays on the Presocratic Enlightenment

    (This unique collection of essays, published together for ...)

    1998
  • Conjectures and Refutations: The Growth of Scientific Knowledge

    (Conjectures and Refutations is one of Karl Popper's most ...)

    1963
  • After The Open Society: Selected Social and Political Writings

    (In this long-awaited volume, Jeremy Shearmur and Piers No...)

    2008
  • Unended Quest: An Intellectual Autobiography

    (At the age of eight, Karl Popper was puzzling over the id...)

    1976
  • All Life is Problem Solving

    (All Life is Problem Solving is a stimulating and provocat...)

    1994
  • The Myth of the Framework: In Defence of Science and Rationality

    (In a career spanning sixty years, Sir Karl Popper has mad...)

    1994
  • Poverty of Historicism

    (Karl Popper's The Poverty of Historicism is one of the mo...)

    1936
  • Quantum Theory and the Schism in Physics: From the Postscript to The Logic of Scientific Discovery

    (Quantum Theory and the Schism in Physics is one of the th...)

    1982
  • Objective Knowledge: An Evolutionary Approach

    (The essays in this volume represent an approach to human ...)

    1972
  • Realism and the Aim of Science: From the Postscript to The Logic of Scientific Discovery

    (Realism and the Aim of Science is one of the three volume...)

    1983
  • The Lesson of this Century: With Two Talks on Freedom and the Democratic State

    (In The Lesson of this Century Popper's purpose is to warn...)

    1992
  • The Self and Its Brain: An Argument for Interactionism

    (The relation between body and mind is one of the oldest r...)

    1977
  • The Open Universe: An Argument for Indeterminism From the Postscript to The Logic of Scientific Discovery 1982
  • Die Zukunft ist offen: Das Altenberger Gesprach : mit den Texten des Wiener Popper-Symposiums 1985
  • A World of Propensities 1990
  • Knowledge and the Body-Mind Problem: In Defence of Interaction 1994

Religion

Popper tended to express Agnostic views, especially towards the end of his life. He also objected to organized religion in cases when he considered it using people's beliefs in unethical ways.

Politics

Popper’s best-known work outside pure scientific philosophy is his 1945 book The Open Society and Its Enemies. In it, he identified Plato, Hegel, and Marx as promoters of totalitarian government and therefore enemies of the open society. As might be expected, academics who approved of the philosophies of Plato, Hegel, and Marx leaped to their defense, accusing Popper of misinterpreting their ideas.

Popper said that although a democracy need not be an open society, liberal democracy was the best way to achieve one. Inspired by the achievements of the Ancient Greeks, he argued against tribal and collectivist societies, asserting that individuals should take responsibility for their own choices and actions.

Popper contended that Fascist or Communist totalitarian societies politicized science, preventing freedom of thought, leading to the degradation of knowledge. Totalitarian governments harmed people and societies by imposing policies on them that had been formulated using false theories.

Views

As Popper represents it, the central problem in the philosophy of science is that of demarcation, i.e., of distinguishing between science and what he terms ‘non-science’, under which heading he ranks, amongst others, logic, metaphysics, psychoanalysis, and Adler’s individual psychology. Popper is unusual amongst contemporary philosophers in that he accepts the validity of the Humean critique of induction, and indeed, goes beyond it in arguing that induction is never actually used in science. However, he does not concede that this entails the skepticism which is associated with Hume, and argues that the Baconian/Newtonian insistence on the primacy of ‘pure’ observation, as the initial step in the formation of theories, is completely misguided: all observation is selective and theory-laden - there are no pure or theory-free observations. In this way he destabilizes the traditional view that science can be distinguished from non-science on the basis of its inductive methodology; in contradistinction to this, Popper holds that there is no unique methodology specific to science. Science, like virtually every other human, and indeed organic, activity, Popper believes, consists largely of problem-solving.

Popper accordingly repudiates induction and rejects the view that it is the characteristic method of scientific investigation and inference, substituting falsifiability in its place. It is easy, he argues, to obtain evidence in favor of virtually any theory, and he consequently holds that such ‘corroboration,’ as he terms it, should count scientifically only if it is the positive result of a genuinely ‘risky’ prediction, which might conceivably have been false. For Popper, a theory is scientific only if it is refutable by a conceivable event. Every genuine test of a scientific theory, then, is logically an attempt to refute or to falsify it, and one genuine counter-instance falsifies the whole theory. In a critical sense, Popper’s theory of demarcation is based upon his perception of the logical asymmetry which holds between verification and falsification: it is logically impossible to conclusively verify a universal proposition by reference to experience (as Hume saw clearly), but a single counter-instance conclusively falsifies the corresponding universal law. In a word, an exception, far from ‘proving’ a rule, conclusively refutes it.

Every genuine scientific theory then, in Popper’s view, is prohibitive, in the sense that it forbids, by implication, particular events or occurrences. As such it can be tested and falsified, but never logically verified. Thus, Popper stresses that it should not be inferred from the fact that a theory has withstood the most rigorous testing, for however long a period of time, that it has been verified; rather we should recognize that such a theory has received a high measure of corroboration and may be provisionally retained as the best available theory until it is finally falsified (if indeed it is ever falsified), and/or is superseded by a better theory.

Popper has always drawn a clear distinction between the logic of falsifiability and its applied methodology. The logic of his theory is utterly simple: if a single ferrous metal is unaffected by a magnetic field it cannot be the case that all ferrous metals are affected by magnetic fields. Logically speaking, a scientific law is conclusively falsifiable although it is not conclusively verifiable. Methodologically, however, the situation is much more complex: no observation is free from the possibility of error - consequently, we may question whether our experimental result was what it appeared to be.

Thus, while advocating falsifiability as the criterion of demarcation for science, Popper explicitly allows for the fact that in practice a single conflicting or counter-instance is never sufficient methodologically to falsify a theory, and that scientific theories are often retained even though much of the available evidence conflicts with them, or is anomalous with respect to them. Scientific theories may, and do, arise genetically in many different ways, and the manner in which a particular scientist comes to formulate a particular theory may be of biographical interest, but it is of no consequence as far as the philosophy of science is concerned. Popper stresses in particular that there is no unique way, no single method such as induction, which functions as the route to scientific theory, a view which Einstein personally endorsed with his affirmation that ‘There is no logical path leading to [the highly universal laws of science]. They can only be reached by intuition, based upon something like an intellectual love of the objects of experience.’ Science, in Popper’s view, starts with problems rather than with observations - it is, indeed, precisely in the context of grappling with a problem that the scientist makes observations in the first instance: his observations are selectively designed to test the extent to which a given theory functions as a satisfactory solution to a given problem.

On this criterion of demarcation physics, chemistry, and (non-introspective) psychology, amongst others, are sciences, psychoanalysis is a pre-science (i.e., it undoubtedly contains useful and informative truths, but until such time as psychoanalytical theories can be formulated in such a manner as to be falsifiable, they will not attain the status of scientific theories), and astrology and phrenology are pseudo-sciences. Formally, then, Popper’s theory of demarcation may be articulated as follows: where a ‘basic statement’ is to be understood as a particular observation-report, then we may say that a theory is scientific if and only if it divides the class of basic statements into the following two non-empty sub-classes: (a) the class of all those basic statements with which it is inconsistent, or which it prohibits - this is the class of its potential falsifiers (i.e., those statements which, if true, falsify the whole theory), and (b) the class of those basic statements with which it is consistent, or which it permits (i.e., those statements which, if true, corroborate it, or bear it out).

Quotations: "You can choose whatever name you like for the two types of government. I personally call the type of government which can be removed without violence "democracy," and the other "tyranny"."

"If we are uncritical we shall always find what we want: we shall look for, and find, confirmations, and we shall look away from, and not see, whatever might be dangerous to our pet theories."

"Whenever a theory appears to you as the only possible one, take this as a sign that you have neither understood the theory nor the problem which it was intended to solve."

"We are social creatures to the inmost centre of our being. The notion that one can begin anything at all from scratch, free from the past, or unindebted to others, could not conceivably be more wrong."

"There is an almost universal tendency, perhaps an inborn tendency, to suspect the good faith of a man who holds opinions that differ from our own opinions. It obviously endangers the freedom and the objectivity of our discussion if we attack a person instead of attacking an opinion or, more precisely, a theory."

"Science may be described as the art of systematic over-simplification - the art of discerning what we may with advantage omit."

"When I speak of reason or rationalism, all I mean is the conviction that we can learn through criticism of our mistakes and errors, especially through criticism by others, and eventually also through self-criticism."

"Our civilization has not yet fully recovered from the shock of its birth - the transition from the tribal or 'closed society', with its submission to magical forces, to the 'open society' which sets free the critical powers of man."

"Nazism and Fascism are thoroughly beaten, but I must admit that their defeat does not mean that barbarism and brutality have been defeated."

"I don't know whether God exists or not. Some forms of atheism are arrogant and ignorant and should be rejected, but agnosticism - to admit that we don't know and to search - is all right. When I look at what I call the gift of life, I feel a gratitude which is in tune with some religious ideas of God. However, the moment I even speak of it, I am embarrassed that I may do something wrong to God in talking about God."

"The whole thing goes back to myths which, though they may have a kernel of truth, are untrue. Why then should the Jewish myth be true and the Indian and Egyptian myths not be true?"

"Although I am not for religion, I do think that we should show respect for anybody who believes honestly."

Membership

Karl Popper was a member of the Royal Society, the British Academy, the American Academy of Arts and Sciences, the Lincean Academy, the Mont Pelerin Society, the International Academy of the History of Science, the National Academy of Sciences, the French Academy of Sciences, and an Honorary member of the Harvard Chapter of Phi Beta Kappa.

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  Royal Society , United Kingdom

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  British Academy , United Kingdom

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  American Academy of Arts and Sciences , United Kingdom

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  Lincean Academy , Italy

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  National Academy of Sciences , United States

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  French Academy of Sciences , France

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  Phi Beta Kappa , United States

• Mont Pelerin Society

• International Academy of the History of Science

Personality

Popper had a rather melancholic personality and took some time to settle on a career. He loved playing the piano, as his mother had done before him. He said that his skills as a pianist never matched hers. In contrast to his work in philosophy, where he challenged the old order, his musical tastes were very traditional – he liked Bach and Beethoven and did not appreciate new classical music such as Arnold Schoenberg’s atonal work.

Interests

• playing the piano

• Philosophers & Thinkers

  Albert Einstein

• Music & Bands

  Johann Sebastian Bach, Ludwig van Beethoven

Connections

Popper married Josephine Anna Henninger (‘Hennie’) in 1930, and she oversaw his welfare with unflagging support and devotion, serving additionally as his amanuensis until her death in 1985. At an early stage of their marriage, they decided that they would never have children, a decision which Popper was able to look back on in later life with apparent equanimity.

Father:

Simon Siegmund Carl Popper

Mother:

Jenny Schiff

Wife:

Josephine Anna Henninger

Friend:

John Eccles

Friend:

Friedrich Hayek

Friend:

Ernst Gombrich

Friend:

Peter Medawar

References

• Philosophy and the Real World: An Introduction to Karl Popper
  1985
• Karl Popper - The Formative Years, 1902-1945: Politics and Philosophy in Interwar Vienna
  2002
• The Viennese Socrates: Karl Popper and the Reconstruction of Progressive Politics
  2012
• Karl Popper, Science and Enlightenment
  2017
• The Cambridge Companion to Popper
  2016
• Karl Popper: Philosophy and Problems
  2008
• Karl Popper
  1973
• The Open Philosophy and the Open Society: A Reply to Dr Karl Popper's Refutations of Marxism
  1987