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Karl Popper

 

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Karl Popper



 
 
Sir
Knight Bachelor

The rank of Knight Bachelor is a part of the British honours system. It is the rank of a man who has been knighted by the monarch but not as a member of one of the organised Chivalric order....
 Karl Raimund Popper CH
Order of the Companions of Honour

The Order of the Companions of Honour is a United Kingdom and Commonwealth of Nations Order . It was founded by George V of the United Kingdom in June 1917, as a reward for outstanding achievements in the arts, literature, music, science, politics, industry, or religion....
, FRS, FBA (28 July 1902 – 17 September 1994) was an Austrian and British philosopher and a professor at the London School of Economics
London School of Economics

The London School of Economics and Political Science, more commonly referred to as The London School of Economics or LSE, is a specialist college of the University of London in London, England....
. He is counted among the most influential philosophers of science
Philosophy of science

The philosophy of science is concerned with the assumptions, foundations, and implications of science. The field is defined by an interest in one of a set of "traditional" problems or an interest in central or foundational concerns in science....
 of the 20th century, and also wrote extensively on social and political philosophy. Popper is known for repudiating the classical observationalist/inductivist
Inductivism

In the philosophy of science inductivism exists both in a classical naive version, which has been highly influential, and in various more sophisticated versions....
 account of scientific method
Scientific method

Scientific method refers to techniques for investigating phenomenon, acquiring new knowledge, or correcting and integrating previous knowledge. To be termed scientific, a method of inquiry must be based on gathering observable, empirical and Measure evidence subject to specific principles of reasoning....
 by advancing empirical falsification
Falsifiability

Falsifiability is the logical possibility that an assertion can be shown false by an observation or a physical experiment. That something is "falsifiable" does not mean it is false; rather, that if it is false, then this can be shown by observation or experiment....
 instead; for his opposition to the classical justificationist account of knowledge which he replaced with critical rationalism
Critical rationalism

Critical rationalism is an epistemological philosophy advanced by Karl Popper. Popper wrote about critical rationalism in his works, The Open Society and its Enemies Volume 2, and Conjectures and Refutations....
, "the first non justificational philosophy of criticism in the history of philosophy" and for his vigorous defense of liberal democracy
Liberal democracy

Liberal democracy is the dominant form of democracy in the 21st century. During the Cold War, liberal democracies were contrasted with the Communist People's Republics or "Popular Democracies", which claimed an alternative conception of democracy....
 and the principles of social criticism
Social criticism

Social criticism analyzes social structures which are seen as flawed and aims at practical solutions by specific measures, radical reform or even revolutionary change....
 which he took to make the flourishing of the "open society
Open society

The open society is a concept originally developed by philosopher Henri Bergson. In open societies, government is responsive and tolerant, and political mechanisms are Transparency and flexible....
" possible.

Popper was born in Vienna
Vienna

Vienna is the Capital of Republic of Austria and also one of the nine states of Austria. Vienna is Austria's primary city, with a population of about 1.7 million...
 (then in Austria-Hungary
Austria-Hungary

Austria-Hungary, also known as the Austro-Hungarian Empire, the Dual Monarchy or the Kaiserlich und k?niglich Monarchy was a state in Central Europe ruled by the House of Habsburg, constitutionally a personal union between the crowns of the Austrian Empire and the Kingdom of Hungary....
) in 1902 to middle-class parents of Jew
Jew

A Jew is a member of the Jewish people, an ethnoreligious group that traces its ancestry to the Israelites or Hebrews of the Ancient Near East....
ish origins, both of whom had converted to Christianity
Christianity

Christianity is a Monotheistic religion #Christian view religion centered on the life and teachings of Jesus as New Testament view on Jesus' life....
.






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Quotations


All things living are in search of a better world.

In Search of a Better World

If we choose freedom, then we must be prepared to perish along with it.

"On Freedom" in All Life is Problem Solving (1999)

No matter how many instances of white swans we may have observed, this does not justify the conclusion that all swans are white.

The Logic of Scientific Discovery (1959)

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.

Objective Knowledge: An Evolutionary Approach (1972)





Encyclopedia


Sir
Knight Bachelor

The rank of Knight Bachelor is a part of the British honours system. It is the rank of a man who has been knighted by the monarch but not as a member of one of the organised Chivalric order....
 Karl Raimund Popper CH
Order of the Companions of Honour

The Order of the Companions of Honour is a United Kingdom and Commonwealth of Nations Order . It was founded by George V of the United Kingdom in June 1917, as a reward for outstanding achievements in the arts, literature, music, science, politics, industry, or religion....
, FRS, FBA (28 July 1902 – 17 September 1994) was an Austrian and British philosopher and a professor at the London School of Economics
London School of Economics

The London School of Economics and Political Science, more commonly referred to as The London School of Economics or LSE, is a specialist college of the University of London in London, England....
. He is counted among the most influential philosophers of science
Philosophy of science

The philosophy of science is concerned with the assumptions, foundations, and implications of science. The field is defined by an interest in one of a set of "traditional" problems or an interest in central or foundational concerns in science....
 of the 20th century, and also wrote extensively on social and political philosophy. Popper is known for repudiating the classical observationalist/inductivist
Inductivism

In the philosophy of science inductivism exists both in a classical naive version, which has been highly influential, and in various more sophisticated versions....
 account of scientific method
Scientific method

Scientific method refers to techniques for investigating phenomenon, acquiring new knowledge, or correcting and integrating previous knowledge. To be termed scientific, a method of inquiry must be based on gathering observable, empirical and Measure evidence subject to specific principles of reasoning....
 by advancing empirical falsification
Falsifiability

Falsifiability is the logical possibility that an assertion can be shown false by an observation or a physical experiment. That something is "falsifiable" does not mean it is false; rather, that if it is false, then this can be shown by observation or experiment....
 instead; for his opposition to the classical justificationist account of knowledge which he replaced with critical rationalism
Critical rationalism

Critical rationalism is an epistemological philosophy advanced by Karl Popper. Popper wrote about critical rationalism in his works, The Open Society and its Enemies Volume 2, and Conjectures and Refutations....
, "the first non justificational philosophy of criticism in the history of philosophy" and for his vigorous defense of liberal democracy
Liberal democracy

Liberal democracy is the dominant form of democracy in the 21st century. During the Cold War, liberal democracies were contrasted with the Communist People's Republics or "Popular Democracies", which claimed an alternative conception of democracy....
 and the principles of social criticism
Social criticism

Social criticism analyzes social structures which are seen as flawed and aims at practical solutions by specific measures, radical reform or even revolutionary change....
 which he took to make the flourishing of the "open society
Open society

The open society is a concept originally developed by philosopher Henri Bergson. In open societies, government is responsive and tolerant, and political mechanisms are Transparency and flexible....
" possible.

Life

Karl Popper was born in Vienna
Vienna

Vienna is the Capital of Republic of Austria and also one of the nine states of Austria. Vienna is Austria's primary city, with a population of about 1.7 million...
 (then in Austria-Hungary
Austria-Hungary

Austria-Hungary, also known as the Austro-Hungarian Empire, the Dual Monarchy or the Kaiserlich und k?niglich Monarchy was a state in Central Europe ruled by the House of Habsburg, constitutionally a personal union between the crowns of the Austrian Empire and the Kingdom of Hungary....
) in 1902 to middle-class parents of Jew
Jew

A Jew is a member of the Jewish people, an ethnoreligious group that traces its ancestry to the Israelites or Hebrews of the Ancient Near East....
ish origins, both of whom had converted to Christianity
Christianity

Christianity is a Monotheistic religion #Christian view religion centered on the life and teachings of Jesus as New Testament view on Jesus' life....
. Popper received a Lutheran upbringing and was educated at the University of Vienna
University of Vienna

The University of Vienna is a public university located in Vienna, Austria. Having opened in 1365, it is one of the oldest universities in Europe....
. His father, Dr. Simon Siegmund Carl Popper, was a doctor of law at the Vienna University and a bibliophile who had 12,000–14,000 volumes in his personal library. Popper inherited from him both the library and the disposition.

In 1919 he became attracted by Marxism
Marxism

Marxism is the political philosophy and practice derived from the work of Karl Marx and Friedrich Engels. Marxism holds at its core a Marxist analysis of Critique of capitalism and a theory of social change....
 and subsequently joined the Association of Socialist School Students and also became a member of the Social Democratic Party of Austria
Social Democratic Party of Austria

The Social Democratic Party of Austria is one of the oldest parties in Austria. The SP? is one of the major parties in Austria and has particularly strong ties to labor unions and the Austrian Chamber of Labour ....
, which was at that time a party that fully adopted the marxist ideology. He soon became disillusioned by the philosophical restraints imposed by the historical materialism
Historical materialism

Historical materialism is a methodological approach to the study of society, economics, and history, first articulated by Karl Marx . Marx himself never used the term but referred to his approach as "the materialist conception of history."...
 of Marx, abandoned the ideology and remained a passive supporter of social liberalism
Social liberalism

Social liberalism is a political position that supports heavier economic regulation and more welfare than other types of liberalism, particularly classical liberalism....
 throughout his life.

In 1928 he earned a doctorate in Psychology and taught secondary school from 1930 to 1936. He published his first book, Logik der Forschung (The Logic of Scientific Discovery
The Logic of Scientific Discovery

Logik der Forschung is a 1934 book by Karl Popper. It was originally written in German language, but reformulated in English language by Popper himself some years later, to be published as The Logic of Scientific Discovery in 1959....
), in 1934. Here, he criticised psychologism
Psychologism

Psychologism is a generic type of position in philosophy according to which psychology plays a central role in grounding or explaining some other, non-psychological type of fact or law....
, naturalism
Naturalism (philosophy)

Naturalism is a philosophical position that all phenomena can be explained in terms of natural causes and natural law. In its broadest and strongest sense, naturalism is the metaphysics position that "nature is all there is and all basic truths are truths of nature." This is generally referred to as metaphysical or ontological natur...
, inductionism
Inductionism

Inductionism is the Philosophy of science where laws are "induction " from sets of data. As an example, one might measure the strength of electrical forces at varying distances from charges and induce the inverse square law of electrostatics....
, and logical positivism
Logical positivism

Logical positivism is a school of philosophy that combines empiricism, the idea that observational evidence is indispensable for knowledge of the world, with a version of rationalism incorporating mathematical and logico-linguistic constructs and deductions in epistemology.See, e.g., : in Stanford Encyclopedia of Philosophy
, and put forth his theory of potential falsifiability
Falsifiability

Falsifiability is the logical possibility that an assertion can be shown false by an observation or a physical experiment. That something is "falsifiable" does not mean it is false; rather, that if it is false, then this can be shown by observation or experiment....
 as the criterion demarcating science from non-science. In 1937, the rise of Nazism
Nazism

Nazism, officially National Socialism , refers to the ideology and practices of the National Socialist German Workers? Party under Adolf Hitler, and the policies adopted by the dictatorial government of Nazi Germany from 1933 to 1945....
 and the threat of the Anschluss
Anschluss

The ' , also known as the ', was the 1938 unification of Austria into Gro?deutschland by Nazi Germany.Austria was merged into Nazi Germany on 12 March 1938....
 led Popper to emigrate to New Zealand, where he became lecturer in philosophy at Canterbury University College
University of Canterbury

The University of Canterbury , New Zealand's second-oldest university, operates in the suburb of Ilam, New Zealand in the city of Christchurch, New Zealand....
 New Zealand
University of New Zealand

The University of New Zealand was the New Zealand university from 1870 to 1961. It was the sole New Zealand university, having a federal structure embracing several constituent colleges at various locations around New Zealand....
 (at Christchurch). In 1946, he moved to England to become reader
Reader (academic rank)

In the academic rank in the United Kingdom and some universities in Australia and New Zealand, reader is the rank between senior lecturer and professor....
 in logic
Logic

Logic is the study of the principles of valid demonstration and inference. Logic is a branch of philosophy, a part of the classical Trivium . The word derives from Greek language ?????? , fem....
 and scientific method
Scientific method

Scientific method refers to techniques for investigating phenomenon, acquiring new knowledge, or correcting and integrating previous knowledge. To be termed scientific, a method of inquiry must be based on gathering observable, empirical and Measure evidence subject to specific principles of reasoning....
 at the London School of Economics
London School of Economics

The London School of Economics and Political Science, more commonly referred to as The London School of Economics or LSE, is a specialist college of the University of London in London, England....
, where he was appointed professor in 1949. He was president of the Aristotelian Society
Aristotelian Society

The Aristotelian Society for the Systematic Study of Philosophy was founded at a meeting on 19 April 1880 which resolved "to constitute a society of about twenty and to include ladies; the society to meet fortnightly, on Mondays at 8 o'clock, at the rooms of the Spelling Reform Association?"...
 from 1958 to 1959. He was knighted
British honours system

The United Kingdom honours system is a means of rewarding individuals' personal bravery, achievement, or service to the United Kingdom. The system consists of three types of award: honours, decorations and medals:...
 by Queen Elizabeth II
Elizabeth II of the United Kingdom

Elizabeth II is the queen regnant of sixteen independent states known as the Commonwealth realms: Monarchy of the United Kingdom, Monarchy of Canada, Monarchy of Australia, Monarchy of New Zealand, Monarchy of Jamaica, Monarchy of Barbados, the Bahamas, Grenada, Papua New Guinea, the Monarchy of the Solomon Islands, Tuvalu, Saint Lucia, Sain...
 in 1965, and was elected a Fellow of the Royal Society
Royal Society

The Royal Society of London for the Improvement of Natural Knowledge, known simply as the Royal Society, or even the Royal, is a learned society for science that was founded in 1660 and is considered by most to be the oldest such society still in existence....
 in 1976. He retired from academic life in 1969, though he remained intellectually active for the rest of his life. He was invested with the Insignia of a Companion of Honour
Order of the Companions of Honour

The Order of the Companions of Honour is a United Kingdom and Commonwealth of Nations Order . It was founded by George V of the United Kingdom in June 1917, as a reward for outstanding achievements in the arts, literature, music, science, politics, industry, or religion....
 in 1982. Popper was a member of the Academy of Humanism and described himself as an agnostic
Agnosticism

Agnosticism is the philosophy view that the logical value of certain claims ? particularly metaphysics claims regarding theology, afterlife or the existence of deity, ghosts, or even ultimate reality ? is unknown or, depending on the form of agnosticism, inherently impossible to prove or disprove....
, showing respect for the moral teachings of Judaism and Christianity.

Popper won many awards and honours in his field, including the Lippincott Award of the American Political Science Association
American Political Science Association

The American Political Science Association is an professional association of political science students and scholars in the United States. Founded in 1903, it publishes three academic journals ....
, the Sonning Prize
Sonning Prize

The Sonning Prize is awarded biennially for outstanding contributions to European culture. A committee headed by the rector of the University of Copenhagen decides among candidates proposed by European universities....
, and fellowships in the Royal Society
Royal Society

The Royal Society of London for the Improvement of Natural Knowledge, known simply as the Royal Society, or even the Royal, is a learned society for science that was founded in 1660 and is considered by most to be the oldest such society still in existence....
, British Academy
British Academy

The British Academy is the United Kingdom's national academy for the humanities and the social sciences. It was established by Royal Charter in 1902, and is a fellowship of more than 800 scholars....
, London School of Economics
London School of Economics

The London School of Economics and Political Science, more commonly referred to as The London School of Economics or LSE, is a specialist college of the University of London in London, England....
, King's College London
King's College London

King's College London is a United Kingdom higher education institution and co-founding constituent college of the University of London. Founded by George IV of the United Kingdom and the Arthur Wellesley, 1st Duke of Wellington in 1829, its royal charter is predated, in England, only by those of the Universities of University of Oxford and Un...
, Darwin College
Darwin College, Cambridge

Darwin College is one of the constituent colleges of the University of Cambridge. Standing on the bank of the River Cam adjacent to Queens' College, Cambridge, it was founded in 1964 by three of the University's older colleges Trinity College, Cambridge, Gonville and Caius College, Cambridge and St John's College, Cambridge....
 Cambridge
University of Cambridge

The University of Cambridge , located in Cambridge, England, is the List of oldest universities in continuous operation university in the Anglosphere....
, and . Austria awarded him the Grand Decoration of Honour in Gold.

Popper died at the age of 92 on 17 September, 1994. After cremation, his ashes were taken to Vienna
Vienna

Vienna is the Capital of Republic of Austria and also one of the nine states of Austria. Vienna is Austria's primary city, with a population of about 1.7 million...
 and buried at Lainzer cemetery adjacent to the ORF
Orf

Orf can refer to:*Orf , a disease found in sheep and goatsORF can refer to:*Open reading frame*Oral reading fluency*ORF , ?sterreichischer Rundfunk...
 Centre, where his wife Josefine Anna Henninger - who had died in Austria several years before - had already been buried.

Popper's philosophy


Philosophy of Science

Popper coined the term critical rationalism
Critical rationalism

Critical rationalism is an epistemological philosophy advanced by Karl Popper. Popper wrote about critical rationalism in his works, The Open Society and its Enemies Volume 2, and Conjectures and Refutations....
 to describe his philosophy. The term indicates his rejection of classical empiricism
Empiricism

In philosophy, empiricism is a theory of knowledge which asserts that knowledge arises from experience. Empiricism is one of several competing views about how we know "things," part of the branch of philosophy called epistemology, or "theory of knowledge"....
, and of the observationalist-inductivist account of science that had grown out of it. Popper argued strongly against the latter, holding that scientific theories are abstract in nature, and can be tested only indirectly, by reference to their implications. He also held that scientific theory, and human knowledge generally, is irreducibly conjectural or hypothetical, and is generated by the creative imagination in order to solve problems that have arisen in specific historico-cultural settings. Logically, no number of positive outcomes at the level of experimental testing can confirm a scientific theory, but a single counterexample is logically decisive: it shows the theory, from which the implication is derived, to be false. Popper's account of the logical asymmetry between verification
Verification theory

The verification theory is a Philosophy theory proposed by the Logical Positivism of the Vienna Circle. A simplified form of the theory states that a proposition's meaning is determined by the method through which it is Empiricism verified....
 and falsifiability
Falsifiability

Falsifiability is the logical possibility that an assertion can be shown false by an observation or a physical experiment. That something is "falsifiable" does not mean it is false; rather, that if it is false, then this can be shown by observation or experiment....
 lies at the heart of his philosophy of science. It also inspired him to take falsifiability as his criterion of demarcation
Demarcation problem

The demarcation problem in the philosophy of science is about how and where to draw the lines around science. The boundaries are commonly drawn between science and non-science, between science and pseudoscience, and between science and religion....
 between what is and is not genuinely scientific: a theory should be considered scientific if and only if it is falsifiable. This led him to attack the claims of both psychoanalysis
Psychoanalysis

Psychoanalysis is a body of ideas developed by Austrian physician Sigmund Freud and his followers, which is devoted to the study of human psychological functioning and behaviour....
 and contemporary Marxism
Marxism

Marxism is the political philosophy and practice derived from the work of Karl Marx and Friedrich Engels. Marxism holds at its core a Marxist analysis of Critique of capitalism and a theory of social change....
 to scientific status, on the basis that the theories enshrined by them are not falsifiable. Popper also wrote extensively against the famous Copenhagen interpretation
Copenhagen interpretation

The Copenhagen interpretation is an Interpretations of quantum mechanics of quantum mechanics. A key feature of quantum mechanics is that the state of every Elementary particle is described by a wavefunction, which is a mathematical representation used to calculate the probability for it to be found in a location, or state of motion....
 of quantum mechanics
Quantum mechanics

Quantum mechanics is a set of principles underlying the most fundamental known description of all physical systems at the microscopic scale . Notable amongst these principles are both a dual wave-like and particle-like behavior of matter and radiation, and prediction of probabilities in situations where classical physics predicts certaintie...
. He strongly disagreed with Niels Bohr
Niels Bohr

Niels Henrik David Bohr was a Denmark physicist who made fundamental contributions to understanding atomic structure and quantum mechanics, for which he received the Nobel Prize in Physics in 1922....
's instrumentalism
Instrumentalism

In the philosophy of science, instrumentalism is the view that concepts and theories are useful instruments whose worth is measured not by whether the concepts and theories are true or false , but by how effective they are in explaining and predicting phenomena....
 and supported Albert Einstein
Albert Einstein

Albert Einstein was a Germany-born theoretical physics. He is best known for his theory of relativity and specifically mass?energy equivalence, expressed by the equation E = mc2....
's realist
Scientific realism

Scientific realism is, at the most general level, the view that the world described by science is the real world, as it is, independent of what we might take it to be....
 approach to scientific theories about the universe. Popper's falsifiability resembles Charles Peirce
Charles Peirce

Charles Sanders Peirce was an American logician, mathematics, Philosophy, and science, born in Cambridge, Massachusetts. Peirce was educated as a chemist and employed as a scientist for 30 years....
's fallibilism
Fallibilism

Fallibilism is the philosophical doctrine that all claims of knowledge could, in principle, be mistaken. Some fallibilists go further, arguing that absolute certainty about knowledge is impossible....
. In Of Clocks and Clouds (1966), Popper remarked that he wished he had known of Peirce's work earlier.

In All Life is Problem Solving, Popper sought to explain the apparent progress of scientific knowledge—how it is that our understanding of the universe seems to improve over time. This problem arises from his position that the truth content of our theories, even the best of them, cannot be verified by scientific testing, but can only be falsified. If so, then how is it that the growth of science appears to result in a growth in knowledge? In Popper's view, the advance of scientific knowledge is an evolutionary process characterised by his formula:

.


In response to a given problem situation , a number of competing conjectures, or tentative theories , are systematically subjected to the most rigorous attempts at falsification possible. This process, error elimination , performs a similar function for science that natural selection
Natural selection

Natural selection is the process by which favorable heritable trait become more common in successive generations of a population of Reproduction organisms, and unfavorable heritable traits become less common, due to differential reproduction of genotypes....
 performs for biological evolution. Theories that better survive the process of refutation are not more true, but rather, more "fit"—in other words, more applicable to the problem situation at hand . Consequently, just as a species' "biological fit" does not predict continued survival, neither does rigorous testing protect a scientific theory from refutation in the future. Yet, as it appears that the engine of biological evolution has produced, over time, adaptive traits equipped to deal with more and more complex problems of survival, likewise, the evolution of theories through the scientific method may, in Popper's view, reflect a certain type of progress: toward more and more interesting problems . For Popper, it is in the interplay between the tentative theories (conjectures) and error elimination (refutation) that scientific knowledge advances toward greater and greater problems; in a process very much akin to the interplay between genetic variation and natural selection.

Where does "truth" fit into all this? As early as 1934 Popper wrote of the search for truth as "one of the strongest motives for scientific discovery." Still, he describes in Objective Knowledge (1972) early concerns about the much-criticised notion of truth as correspondence
Correspondence theory of truth

The correspondence theory of truth states that the truth or falsity of a statement is determined only by how it relates to the world, and whether it accurately describes that world....
. Then came the semantic theory of truth
Semantic theory of truth

The semantic theory of truth holds that any assertion that a Sentence is truth can be made only as a formal requirement regarding the language in which the proposition itself is expressed....
 formulated by the logician Alfred Tarski
Alfred Tarski

Alfred Tarski was a Poles logician and mathematician. Educated in the Warsaw School of Mathematics and philosophy, he emigrated to the USA in 1939, and taught and did research in mathematics at the University of California, Berkeley, from 1942 until his death....
 and published in 1933. Popper writes of learning in 1935 of the consequences of Tarski's theory, to his intense joy. The theory met critical objections to truth
Truth

semantic fields for the word truth extend from honesty, good faith, and sincerity in general, to agreement with fact or reality in particular....
 as correspondence and thereby rehabilitated it. The theory also seemed, in Popper's eyes, to support metaphysical realism and the regulative idea of a search for truth.

According to this theory, the conditions for the truth of a sentence as well as the sentences themselves are part of a metalanguage
Metalanguage

In logic and linguistics, a metalanguage is a language used to make statements about statements in another language which is called the object language....
. So, for example, the sentence "Snow is white" is true if and only if snow is white. Although many philosophers have interpreted, and continue to interpret, Tarski's theory as a deflationary theory
Deflationary theory of truth

The deflationary theory of truth is a family of theories which all have in common the claim that assertions that predicate truth of a statement do not attribute a property called truth to such a statement....
, Popper refers to it as a theory in which "is true" is replaced with "corresponds to the facts." He bases this interpretation on the fact that examples such as the one described above refer to two things: assertions and the facts to which they refer. He identifies Tarski's formulation of the truth conditions of sentences as the introduction of a "metalinguistic predicate" and distinguishes the following cases:

  1. "John called" is true.
  2. "It is true that John called."


The first case belongs to the metalanguage whereas the second is more likely to belong to the object language. Hence, "it is true that" possesses the logical status of a redundancy. "Is true", on the other hand, is a predicate necessary for making general observations such as "John was telling the truth about Phillip."

Upon this basis, along with that of the logical content of assertions (where logical content is inversely proportional to probability), Popper went on to develop his important notion of verisimilitude
Verisimilitude

Verisimilitude in its literary context is defined as the fact or quality of being verisimilar, the appearance of being true or real; likeness or resemblance of the truth, reality or a fact's probability....
 or "truthlikeness".

The intuitive idea behind verisimilitude is that the assertions or hypotheses of scientific theories can be objectively measured with respect to the amount of truth and falsity that they imply. And, in this way, one theory can be evaluated as more or less true than another on a quantitative basis which, Popper emphasizes forcefully, has nothing to do with "subjective probabilities" or other merely "epistemic" considerations.

The simplest mathematical formulation that Popper gives of this concept can be found in the tenth chapter of Conjectures and Refutations
Conjectures and Refutations

Conjectures and Refutations: The Growth of Scientific Knowledge is a book written by philosopher Karl Popper.Published in 1963 by Routledge, this book is a collection of his lectures and papers that summarised his thoughts on the philosophy of science....
.
. Here he defines it as:



where is the verisimilitude of a, is a measure of the content of truth of a, and is a measure of the content of the falsity of a.

Knowledge, for Popper, was objective, both in the sense that it is objectively true (or truthlike), and also in the sense that knowledge has an ontological status (i.e., knowledge as object) independent of the knowing subject (Objective Knowledge: An Evolutionary Approach, 1972). He proposed three worlds (see Popperian cosmology
Popperian cosmology

Popperian cosmology is Karl Popper's philosophical theory of reality that includes three interacting worlds, called World 1, World 2 and World 3....
): World One, being the physical world, or physical states; World Two, being the world of mind, or mental states, ideas, and perceptions; and World Three, being the body of human knowledge expressed in its manifold forms, or the products of the second world made manifest in the materials of the first world (i.e.–books, papers, paintings, symphonies, and all the products of the human mind). World Three, he argued, was the product of individual human beings in exactly the same sense that an animal path is the product of individual animals, and that, as such, has an existence and evolution independent of any individual knowing subjects. The influence of World Three, in his view, on the individual human mind (World Two) is at least as strong as the influence of World One. In other words, the knowledge held by a given individual mind owes at least as much to the total accumulated wealth of human knowledge, made manifest, as to the world of direct experience. As such, the growth of human knowledge could be said to be a function of the independent evolution of World Three. Many contemporary philosophers have not embraced Popper's Three World conjecture, due mostly, it seems, to its resemblance to Cartesian dualism.

Political philosophy

In The Open Society and Its Enemies
The Open Society and Its Enemies

The Open Society and Its Enemies, is an influential two-volume work by Karl Popper written during World War II. Failing to find a publisher in the United States, it was first printed in London, by Routledge, in 1945....
 and The Poverty of Historicism
The Poverty of Historicism

The Poverty of Historicism is a book by twentieth century philosopher Karl Popper which seeks to persuade the reader of both the danger and the bankruptcy of the idea of historicism....
, Popper developed a critique of historicism
Historicism

Historicism refers to philosophy theories that include one or both of two claims:# that there is an organic succession of developments, a notion also known as historism , and/or;...
 and a defence of the 'Open Society'. Historicism is the theory that history develops inexorably and necessarily according to knowable general laws towards a determinate end. Popper argued that this view is the principal theoretical presupposition underpinning most forms of authoritarianism
Authoritarianism

Authoritarianism describes a form of government characterized by an emphasis on the authority of the state in a republic or union. It is a political system controlled by nonelected rulers who usually permit some degree of individual freedom....
 and totalitarianism
Totalitarianism

Totalitarianism is a concept used to describe political systems whereby a state regulates nearly every aspect of public and private life. Totalitarian regimes or movements maintain themselves in political power by means of an official all-embracing ideology and propaganda disseminated through the state-controlled mass media, single-party st...
. He argued that historicism is founded upon mistaken assumptions regarding the nature of scientific law and prediction. Since the growth of human knowledge is a causal factor in the evolution of human history, and since "no society can predict, scientifically, its own future states of knowledge", it follows, he argued, that there can be no predictive science of human history. For Popper, metaphysical and historical indeterminism go hand in hand.

In a 1992 lecture, Popper explained the connection between his political philosophy and his philosophy of science. As he stated, he was in his early years impressed by communism and also active in the Austrian Communist party. What had a profound effect on him was an event that happened in 1918: during a riot, caused by the Communists, the police shot several people, including some of Popper's friends. When Popper later told the leaders of the Communist party about this, they responded by stating that this loss of life was necessary in working towards the inevitable workers' revolution. This statement did not convince Popper and he started to think about what kind of reasoning would justify such a statement. He later concluded that there could not be any justification for it, and this was the start of his later criticism of historicism.

Problem of Induction

Among his contributions to philosophy is his attempt to answer the philosophical problem of induction
Problem of induction

The problem of induction is the philosophy question of whether inductive reasoning leads to truth. That is, what is the justification for either:...
. The problem, in basic terms, can be understood by example: given that the sun has risen every day for as long as anyone can remember, what is the rational proof that it will rise tomorrow? How can one rationally prove that past events will continue to repeat in the future, just because they have repeated in the past? Popper's reply is characteristic, and ties in with his criterion of falsifiability. He states that while there is no way to prove that the sun will rise, we can formulate a theory that every day the sun will rise—if it does not rise on some particular day, our theory will be disproved, but at present it is confirmed. Since it is a very well-tested theory, we have every right to believe that it accurately represents reality, so far as we know.

This may be a true description of the pragmatic approach to knowledge adopted by the scientific method, but it does not in itself address the philosophical problem. As Stephen Hawking
Stephen Hawking

Stephen William Hawking Companion of Honour, Commander of the British Empire, Fellow of the Royal Society, Fellow of the Royal Society of Arts, Doctor of Philosophy is a British Theoretical physics....
 explains, "No matter how many times the results of experiments agree with some theory, you can never be sure that the next time the result will not contradict the theory." It may be pragmatically useful to accept a well-tested theory as true until it is falsified, but this does not solve the philosophical problem of induction. As Bertrand Russell
Bertrand Russell

Bertrand Arthur William Russell, 3rd Earl Russell, Order of Merit , Fellow of the Royal Society , was a British people philosopher, mathematical logic, mathematician, historian, advocate for social reform, and pacifism....
 put it, "the general principles of science . . . are believed because mankind have found innumerable instances of their truth and no instances of their falsehood. But this affords no evidence for their truth in the future, unless the inductive principle is assumed." In essence, Popper addressed justification for belief ("why do you believe") that the sun will rise tomorrow, not justification for the fact ("how do you know") that it will, which is the crux of the philosophical problem. Said another way, Popper addressed the psychological causes of our belief in the validity of induction without trying to provide logical reasons for it. In this way, he provided a psychological account of the use of induction, but left the philosophical ground of induction as a valid mode of knowledge unaccounted for.

Issue of Darwinism

Karl Popper famously stated "Darwinism is not a testable scientific theory, but a metaphysical research program." In the same paper, he continued "And yet, the theory is invaluable. I do not see how, without it, our knowledge could have grown as it has done since Darwin. In trying to explain experiments with bacteria which become adapted to, say, penicillin, it is quite clear that we are greatly helped by the theory of natural selection. Although it is metaphysical, it sheds much light upon very concrete and very practical researches. It allows us to study adaptation to a new environment (such as a penicillin-infested environment) in a rational way: it suggests the existence of a mechanism of adaptation, and it allows us even to study in detail the mechanism at work." He also noted that theism presented as explaining adaptation "was worse than an open admission of failure, for it created the impression that an ultimate explanation had been reached"

He later said "When speaking here of Darwinism, I shall speak always of today's theory - that is Darwin's own theory of natural selection supported by the Mendelian theory of heredity, by the theory of the mutation and recombination of genes in a gene pool, and by the decoded genetic code. This is an immensely impressive and powerful theory. The claim that it completely explains evolution is of course a bold claim, and very far from being established. All scientific theories are conjectures, even those that have successfully passed many severe and varied tests. The Mendelian underpinning of modern Darwinism has been well tested, and so has the theory of evolution which says that all terrestrial life has evolved from a few primitive unicellular organisms, possibly even from one single organism. "

He explained that the difficulty of testing had led some people to describe natural selection as a tautology
Tautology

Tautology may refer to:*Tautology , a statement of propositional logic which holds for all truth values of its atomic propositions*Tautology , use of redundant language...
, and that he too had in the past described the theory as 'almost tautological', and had tried to explain how the theory could be untestable (as is a tautology) and yet of great scientific interest. His "solution was that the doctrine of natural selection is a most successful metaphysical research programme. It raises detailed problems in many fields, and it tells us what we would expect of an acceptable solution of these problems. I still believe that natural selection works in this way as a research programme. Nevertheless, I have changed my mind about the testability and logical status of the theory of natural selection; and I am glad to have an opportunity to make a recantation."

Influence

By all accounts, Popper has played a vital role in establishing the philosophy of science
Philosophy of science

The philosophy of science is concerned with the assumptions, foundations, and implications of science. The field is defined by an interest in one of a set of "traditional" problems or an interest in central or foundational concerns in science....
 as a vigorous, autonomous discipline within analytic philosophy
Analytic philosophy

Analytic philosophy is a generic term for a style of philosophy that came to dominate English-speaking countries in the 20th century. In the United States, United Kingdom, Canada, Scandinavia, Australia, and New Zealand the overwhelming majority of university philosophy departments identify themselves as "analytic" departments....
, through his own prolific and influential works, and also through his influence on his own contemporaries and students. Popper founded in 1946 the Department of Philosophy, Logic and Scientific Method at the London School of Economics
London School of Economics

The London School of Economics and Political Science, more commonly referred to as The London School of Economics or LSE, is a specialist college of the University of London in London, England....
 and there lectured and influenced both Imre Lakatos
Imre Lakatos

Imre Lakatos was a philosopher of Philosophy of mathematics and Philosophy of science, most famous today worldwide for his thesis of the fallibility of mathematics and its 'methodology of proofs and refutations', and also for introducing the concept of the 'research programme' in his methodology of scientific research programmes....
 and Paul Feyerabend
Paul Feyerabend

Paul Karl Feyerabend was an Austrian-born philosopher of science best known for his work as a professor of philosophy at the University of California, Berkeley, where he worked for three decades ....
, two of the foremost philosophers of science in the next generation of philosophy of science. (Lakatos significantly modified Popper's position, and Feyerabend repudiated it entirely, but the work of both is deeply influenced by Popper and engaged with many of the problems that Popper set.)

While there is some dispute as to the matter of influence, Popper had a long-standing and close friendship with economist Friedrich Hayek
Friedrich Hayek

Friedrich August von Hayek Order of the Companions of Honour was an Austrian economist and philosopher known throughout the world for his defense of classical liberalism and free market capitalism against socialism and collectivism thought....
, who was also brought to the London School of Economics
London School of Economics

The London School of Economics and Political Science, more commonly referred to as The London School of Economics or LSE, is a specialist college of the University of London in London, England....
 from Vienna. Each found support and similarities in each other's work, citing each other often, though not without qualification. In a letter to Hayek in 1944, Popper stated, "I think I have learnt more from you than from any other living thinker, except perhaps Alfred Tarski
Alfred Tarski

Alfred Tarski was a Poles logician and mathematician. Educated in the Warsaw School of Mathematics and philosophy, he emigrated to the USA in 1939, and taught and did research in mathematics at the University of California, Berkeley, from 1942 until his death....
." (See Hacohen, 2000). Popper dedicated his Conjectures and Refutations
Conjectures and Refutations

Conjectures and Refutations: The Growth of Scientific Knowledge is a book written by philosopher Karl Popper.Published in 1963 by Routledge, this book is a collection of his lectures and papers that summarised his thoughts on the philosophy of science....
 to Hayek. For his part, Hayek dedicated a collection of papers, Studies in Philosophy, Politics, and Economics, to Popper, and in 1982 said, "...ever since his Logik der Forschung first came out in 1934, I have been a complete adherent to his general theory of methodology." (See Weimer and Palermo, 1982).

Popper also had long and mutually influential friendships with art historian Ernst Gombrich
Ernst Gombrich

Sir Ernst Hans Josef Gombrich, Order of Merit, Order of the British Empire was an Austrian-born art historian who spent most of his working life in the United Kingdom....
, biologist Peter Medawar
Peter Medawar

Sir Peter Brian Medawar, Order of Merit, Commander of the Order of the British Empire, Fellow of the Royal Society was a Brazilian-born Lebanon-United Kingdom scientist best known for his work on how the immune system rejects or accepts tissue transplants....
, and neuro-scientist John Carew Eccles
John Carew Eccles

Sir John Carew Eccles, Order of Australia Royal Society Royal Australasian College of Physicians Royal Society of New Zealand Australian Academy of Science was an Australian neurophysiologist who won the 1963 Nobel Prize in Physiology or Medicine for his work on the synapse....
.

Popper's influence, both through his work in philosophy of science and through his political philosophy, has also extended beyond the academy. Among Popper's students and advocates at the London School of Economics
London School of Economics

The London School of Economics and Political Science, more commonly referred to as The London School of Economics or LSE, is a specialist college of the University of London in London, England....
 is the multibillionaire investor George Soros
George Soros

George Soros is an United States currency Speculation, stock investor, businessman, philanthropist, and activism.Soros is estimated to be worth around $9.0 billion in net worth; he is ranked by Forbes as the List of billionaires ....
, who says his investment strategies are modelled on Popper's understanding of the advancement of knowledge through, the distinctly Hegelian idea of falsification
Falsifiability

Falsifiability is the logical possibility that an assertion can be shown false by an observation or a physical experiment. That something is "falsifiable" does not mean it is false; rather, that if it is false, then this can be shown by observation or experiment....
. Among Soros's philanthropic
Philanthropy

Philanthropy derives from Latin, meaning "to love people". Philanthropy is the act of donation money, goods, services, time and/or effort to support a socially beneficial cause, with a defined objective and with no financial or material reward to the donor....
 foundations is the Open Society Institute
Open Society Institute

The Open Society Institute , a private operating and Grant foundation, aims to shape public policy to promote democracy governance, human rights, and Economic reform, legal, and social reform....
, a think-tank named in honour of Popper's The Open Society and Its Enemies
The Open Society and Its Enemies

The Open Society and Its Enemies, is an influential two-volume work by Karl Popper written during World War II. Failing to find a publisher in the United States, it was first printed in London, by Routledge, in 1945....
, which Soros founded to advance the Popperian defense of the open society
Open society

The open society is a concept originally developed by philosopher Henri Bergson. In open societies, government is responsive and tolerant, and political mechanisms are Transparency and flexible....
 against authoritarianism
Authoritarianism

Authoritarianism describes a form of government characterized by an emphasis on the authority of the state in a republic or union. It is a political system controlled by nonelected rulers who usually permit some degree of individual freedom....
 and totalitarianism
Totalitarianism

Totalitarianism is a concept used to describe political systems whereby a state regulates nearly every aspect of public and private life. Totalitarian regimes or movements maintain themselves in political power by means of an official all-embracing ideology and propaganda disseminated through the state-controlled mass media, single-party st...
.

Popperian philosophy also inspired the creation of Taking Children Seriously
Taking Children Seriously

Taking Children Seriously is a parenting movement and educational philosophy whose central idea is that is possible and desirable to raise and educate children without either doing anything to them against their will, or making them do anything against their will....
, a movement which noticed that Popper's general theory of knowledge creation does not differentiate between adults and children.

Critics


Criticism of his philosophy of science


Most criticisms of Popper's philosophy are of the falsification, or error elimination, element in his account of problem solving. In interpreting these, it is important to bear in mind the aims of his idea. It is intended as an ideal, practical method of effective human problem solving; as such, the current conclusions of science are stronger than pseudo-sciences or non-sciences, insofar as they have survived this particularly vigorous selection method. He does not argue that any such conclusions are therefore true, or that this describes the actual methods of any particular scientist.

Rather, it is a recommended ideal method that, if enacted by a system or community, will over time lead to slow but steady progress of a sort (relative to how well the system or community enacts the method). It has been suggested that Popper's ideas are often mistaken for a hard logical account of truth because of the historical co-incidence of their appearing at the same time as logical positivism
Logical positivism

Logical positivism is a school of philosophy that combines empiricism, the idea that observational evidence is indispensable for knowledge of the world, with a version of rationalism incorporating mathematical and logico-linguistic constructs and deductions in epistemology.See, e.g., : in Stanford Encyclopedia of Philosophy
, the followers of which mistook his aims for their own (Bryan Magee 1973: Popper (Modern Masters series)).

The Quine-Duhem thesis
Confirmation holism

Confirmation holism, also called epistemological holism is the claim that a single scientific theory cannot be tested in isolation; a test of one theory always depends on other theories and hypotheses....
 argues that it's impossible to test a single hypothesis on its own, since each one comes as part of an environment of theories. Thus we can only say that the whole package of relevant theories has been collectively falsified, but cannot conclusively say which element of the package must be replaced. An example of this is given by the discovery of the planet Neptune: when the motion of Uranus was found not to match the predictions of Newton's laws, the theory "There are seven planets in the solar system" was rejected, and not Newton's laws themselves. Popper discussed this critique of naïve falsificationism
Falsifiability

Falsifiability is the logical possibility that an assertion can be shown false by an observation or a physical experiment. That something is "falsifiable" does not mean it is false; rather, that if it is false, then this can be shown by observation or experiment....
 in Chapters 3 & 4 of The Logic of Scientific Discovery
The Logic of Scientific Discovery

Logik der Forschung is a 1934 book by Karl Popper. It was originally written in German language, but reformulated in English language by Popper himself some years later, to be published as The Logic of Scientific Discovery in 1959....
. For Popper, theories are accepted or rejected via a sort of selection process. Theories that say more about the way things appear are to be preferred over those that do not; the more generally applicable a theory is, the greater its value. Thus Newton’s laws, with their wide general application, are to be preferred over the much more specific “the solar system has seven planets”.

Thomas Kuhn’s influential book The Structure of Scientific Revolutions
The Structure of Scientific Revolutions

The Structure of Scientific Revolutions , by Thomas Samuel Kuhn, is an analysis of the history of science. Its publication was a landmark event in the sociology of knowledge, and popularized the terms paradigm and paradigm shift....
 argued that scientists work in a series of paradigm
Paradigm

The word paradigm has been used in linguistics and science to describe distinct concepts.To the 1960s, the word was specific to grammar: the 1900 Merriam-Webster dictionary defines its technical use only in the context of grammar or, in rhetoric, as a term for an illustrative parable or fable....
s, and found little evidence of scientists actually following a falsificationist methodology. Popper's student Imre Lakatos
Imre Lakatos

Imre Lakatos was a philosopher of Philosophy of mathematics and Philosophy of science, most famous today worldwide for his thesis of the fallibility of mathematics and its 'methodology of proofs and refutations', and also for introducing the concept of the 'research programme' in his methodology of scientific research programmes....
 attempted to reconcile Kuhn’s work with falsificationism by arguing that science progresses by the falsification of research programs rather than the more specific universal statements
Universal quantification

In predicate logic, universal quantification formalizes the notion that something is true for everything, or every relevant thing.The resulting statement is a universally quantified statement, and we have universally quantified over the predicate....
 of naïve falsificationism. Another of Popper’s students Paul Feyerabend
Paul Feyerabend

Paul Karl Feyerabend was an Austrian-born philosopher of science best known for his work as a professor of philosophy at the University of California, Berkeley, where he worked for three decades ....
 ultimately rejected any prescriptive methodology, and argued that the only universal method characterizing scientific progress was anything goes.

Popper seems to have anticipated Kuhn's observations. In his collection Conjectures and Refutations
Conjectures and Refutations

Conjectures and Refutations: The Growth of Scientific Knowledge is a book written by philosopher Karl Popper.Published in 1963 by Routledge, this book is a collection of his lectures and papers that summarised his thoughts on the philosophy of science....
: The Growth of Scientific Knowledge
(Harper & Row, 1963), Popper writes, "Science must begin with myths, and with the criticism of myths; neither with the collection of observations, nor with the invention of experiments, but with the critical discussion of myths, and of magical techniques and practices. The scientific tradition is distinguished from the pre-scientific tradition in having two layers. Like the latter, it passes on its theories; but it also passes on a critical attitude towards them. The theories are passed on, not as dogmas, but rather with the challenge to discuss them and improve upon them."

Another objection is that it is not always possible to demonstrate falsehood definitively, especially if one is using statistical
Statistical significance

In statistics, a result is called statistically significant if it is unlikely to have occurred by chance. "A statistically significant difference" simply means there is statistical evidence that there is a difference; it does not mean the difference is necessarily large, important, or significant in the common meaning of the word....
 criteria to evaluate a null hypothesis
Null hypothesis

In statistics, a null hypothesis is a concept which arises in the context of statistical hypothesis testing. A common convention is to use the symbol H0 to denote the null hypothesis....
. More generally it is not always clear, if evidence contradicts a hypothesis, that this is a sign of flaws in the hypothesis rather than of flaws in the evidence. However, this is a misunderstanding of what Popper's philosophy of science sets out to do. Rather than offering a set of instructions that merely need to be followed diligently to achieve science, Popper makes it clear in The Logic of Scientific Discovery
The Logic of Scientific Discovery

Logik der Forschung is a 1934 book by Karl Popper. It was originally written in German language, but reformulated in English language by Popper himself some years later, to be published as The Logic of Scientific Discovery in 1959....
 that his belief is that the resolution of conflicts between hypotheses and observations can only be a matter of the collective judgment of scientists, in each individual case.

Popper's falsificationism can be questioned logically, by asking about statements such as "There are black hole
Black hole

In general relativity, a black hole is a region of space in which the gravitational field is so powerful that nothing, including electromagnetic radiation , can escape its pull after having fallen past its event horizon....
s", which cannot be falsified by any possible observation yet seem to be scientifically legitimate claims. Similarly, it is not clear how Popper would deal with a statement like "for every metal, there is a temperature at which it will melt", which can neither be confirmed nor falsified by any possible observation, yet which seems to be a valid scientific hypothesis. These examples were pointed out by Carl Gustav Hempel
Carl Gustav Hempel

Carl Gustav "Peter" Hempel was a Philosophy of science and a major figure in 20th-century logical positivism. He is especially well-known for his articulation of the Deductive-nomological model of scientific explanation, which was considered the "standard model" of scientific explanation during the 1950s and 1960's....
. Hempel came to acknowledge that Logical Positivism's verificationism was untenable, but argued that falsificationism was equally untenable on logical grounds alone. The simplest response to this is that, because Popper describes how theories attain, maintain and lose scientific status, individual consequences of currently accepted scientific theories are scientific in the sense of being part of tentative scientific knowledge, and both of Hempel's examples fall under this category. For instance, atomic theory
Atomic theory

In chemistry and physics, atomic theory is a theory of the nature of matter, which states that matter is composed of discrete units called atoms, as opposed to the obsolete notion that matter could be divided into any arbitrarily small quantity....
 implies that all metals melt at some temperature.

An early German-speaking adversary of so-called critical rationalism, Karl-Otto Apel elaborated a comprehensive refutation of the philosophy of Karl Raimund Popper: In Transformation der philosophie (1973), Apel charged Popper with being guilty of, amongst other things, a pragmatic contradiction.

Other criticisms


Other critics seek to vindicate the claims of historicism
Historicism

Historicism refers to philosophy theories that include one or both of two claims:# that there is an organic succession of developments, a notion also known as historism , and/or;...
 or holism
Holism

Holism is the idea that all the properties of a given system cannot be determined or explained by its component parts alone. Instead, the system as a whole determines in an important way how the parts behave....
 to intellectual respectability, or psychoanalysis
Psychoanalysis

Psychoanalysis is a body of ideas developed by Austrian physician Sigmund Freud and his followers, which is devoted to the study of human psychological functioning and behaviour....
 or Marxism
Marxism

Marxism is the political philosophy and practice derived from the work of Karl Marx and Friedrich Engels. Marxism holds at its core a Marxist analysis of Critique of capitalism and a theory of social change....
 to scientific status. It has been argued that Popper's student Imre Lakatos
Imre Lakatos

Imre Lakatos was a philosopher of Philosophy of mathematics and Philosophy of science, most famous today worldwide for his thesis of the fallibility of mathematics and its 'methodology of proofs and refutations', and also for introducing the concept of the 'research programme' in his methodology of scientific research programmes....
, for example, transformed Popper's philosophy using historicist and updated Hegelian historiographic ideas. (subscription and/or fee required)

Charles Taylor
Charles Taylor (philosopher)

Charles Margrave Taylor, Order of Canada, National Order of Quebec, Royal Society of Canada is a Canadian philosopher from Montreal, Quebec, Canada, who has made significant contributions to political philosophy, philosophy of social science, and the history of philosophy....
 accuses Popper of exploiting his worldwide fame as an epistemologist to diminish the importance of philosophers of the 20th century continental tradition
Continental philosophy

Continental philosophy, in contemporary usage, refers to a set of traditions of 19th and 20th century philosophy from mainland Europe. This sense of the term originated among English-speaking philosophers in the second half of the 20th century, who found it useful for referring to a range of thinkers and traditions outside the analytic philo...
. According to Taylor, Popper's criticisms are completely baseless, but they are received with an attention and respect that Popper's "intrinsic worth hardly merits". William W. Bartley defended Popper against such allegations: "Sir Karl Popper is not really a participant in the contemporary professional philosophical dialogue; quite the contrary, he has ruined that dialogue. If he is on the right track, then the majority of professional philosophers the world over has wasted or is wasting their intellectual careers. The gulf between Popper's way of doing philosophy and that of the bulk of professional philosophers is as great as that between astronomy and astrology."(deposit account required)

In 2004 philosopher and psychologist
Psychologist

"Psychologist" is an academic, occupational or professional title describing individuals who are either: * social scientists conducting research and/or teaching psychology in a college or university;...
 Michel ter Hark (Groningen
Groningen (city)

||-| |-| |-| |-| |-| |-| |-| |-| |}Groningen is the capital city of the province of Groningen in the Netherlands. With a population of 185,000, it is by far the largest city in the north of the Netherlands....
, The Netherlands) published a book, called Popper, Otto Selz and the rise of evolutionary epistemology, ISBN 0521830745, in which he claimed that Popper took some of his ideas from his tutor, the German-Jewish psychologist Otto Selz
Otto Selz

Otto Selz, was a Germany psychologist from Munich, Kingdom of Bavaria, who formulated the first Association theory of thinking, in 1913. Selz used the method of introspection, but unlike his predecessors, his theory developed without the use of images and associations....
. Selz himself never published his ideas, partly because of the rise of Nazism
Nazism

Nazism, officially National Socialism , refers to the ideology and practices of the National Socialist German Workers? Party under Adolf Hitler, and the policies adopted by the dictatorial government of Nazi Germany from 1933 to 1945....
 which forced him to quit his work in 1933, and the prohibition of referring to Selz' work.

Karl Popper, the historian of ideas and his scholarship, is severely criticized and rebuked in many academic quarters, especially for his writings on Plato and Hegel.

According to Karl Popper, a theory is scientific only in so far as it is falsifiable, and should be given up as soon as it is falsified. By applying Poppers account of scientific method, John Gray's Straw Dogs goes onto say that this would have killed the theories of Darwin and Einstein at birth. When they were first advanced, each of them was at odds with some available evidence; only later did evidence come available that gave them crucial suport.

See also

  • Popperian cosmology
    Popperian cosmology

    Popperian cosmology is Karl Popper's philosophical theory of reality that includes three interacting worlds, called World 1, World 2 and World 3....
  • Evolutionary epistemology
    Evolutionary epistemology

    Evolutionary epistemology refers to two distinct topics: it is a subfield of naturalized epistemology as well as a theory in epistemology about the growth of knowledge....
  • Liberalism
    Liberalism

    Liberalism is a broad class of political philosophy that considers individualism liberty and equality to be the most important political goals....
  • Liberalism in Austria
    Liberalism in Austria

    This article gives an overview of liberalism in Austria. It is limited to liberalism political party with substantial support, mainly proved by having had a representation in parliament....
  • Contributions to liberal theory
    Contributions to liberal theory

    This is a partial list of individual contributions to Liberalism on a worldwide scale. These individuals are strongly associated philosophers of the Enlightenment....
  • Calculus of predispositions
    Calculus of predispositions

    'Calculus of Predispositions' is a basic part of Predispositioning Theory and belongs to the indeterministic procedures.?The key component of any indeterministic procedure is the evaluation of a position....
  • Predispositioning Theory
    Predispositioning Theory

    Predispositioning Theory was founded by Aron Katsenelinboigen , a Professor in Wharton School who dealt with indeterministic systems such as chess, business, economics, and other fields of knowledge and also made an essential step forward in elaboration of styles and methods of decision-making....
  • Popper's experiment
    Popper's experiment

    Popper's experiment is an experiment proposed by the 20th century philosopher of science Karl Popper, to test the standard interpretation of Quantum mechanics....
     (quantum mechanics)


Bibliography

  • The Two Fundamental Problems of the Theory of Knowledge, 1930–33 (as a typescript circulating as Die beiden Grundprobleme der Erkenntnistheorie; as a German book 1979, as English translation 2008), ISBN 0415394317
  • The Logic of Scientific Discovery
    The Logic of Scientific Discovery

    Logik der Forschung is a 1934 book by Karl Popper. It was originally written in German language, but reformulated in English language by Popper himself some years later, to be published as The Logic of Scientific Discovery in 1959....
    , 1934 (as Logik der Forschung, English translation 1959), ISBN 0415278449
  • The Poverty of Historicism
    The Poverty of Historicism

    The Poverty of Historicism is a book by twentieth century philosopher Karl Popper which seeks to persuade the reader of both the danger and the bankruptcy of the idea of historicism....
    , 1936 (private reading at a meeting in Brussels, 1944/45 as a series of journal articles in Econometrica, 1957 a book), ISBN 0415065690
  • The Open Society and Its Enemies
    The Open Society and Its Enemies

    The Open Society and Its Enemies, is an influential two-volume work by Karl Popper written during World War II. Failing to find a publisher in the United States, it was first printed in London, by Routledge, in 1945....
    , 1945 Vol 1 ISBN 0415290635, Vol 2 ISBN 0415290635
  • Quantum Theory and the Schism in Physics, 1956/57 (as privately circulated galley proofs; published as a book 1982), ISBN 0415091128
  • The Open Universe: An Argument for Indeterminism, 1956/57 (as privately circulated galley proofs; published as a book 1982), ISBN 0415078652
  • Realism and the Aim of Science, 1956/57 (as privately circulated galley proofs; published as a book 1983), ISBN 0091514509
  • Conjectures and Refutations
    Conjectures and Refutations

    Conjectures and Refutations: The Growth of Scientific Knowledge is a book written by philosopher Karl Popper.Published in 1963 by Routledge, this book is a collection of his lectures and papers that summarised his thoughts on the philosophy of science....
    : The Growth of Scientific Knowledge
    , 1963, ISBN 0415043182
  • Objective Knowledge: An Evolutionary Approach, 1972, Rev. ed., 1979, ISBN 0198750242
  • Unended Quest; An Intellectual Autobiography, 1976, ISBN 0415285909
  • The Self and Its Brain: An Argument for Interactionism (with Sir John C. Eccles), 1977, ISBN 0415058988
  • article by Popper, Dialectica 1978
  • In Search of a Better World, 1984, a collection of Popper’s essays and lectures covering a range of subjects from the beginning of scientific speculation in classical Greece to the need for a new professional ethic based on the ideas of tolerance and intellectual responsibility; "All things living are in search of a better world."; Karl Popper, from the Preface of the book. ISBN 0415135486
  • Die Zukunft ist offen (The Future is Open) (with Konrad Lorenz
    Konrad Lorenz

    Konrad Zacharias Lorenz was an Austrian zoology, animal psychology, ornithologist and Nobel Prize winner. He is often regarded as one of the founders of modern ethology, developing an approach that began with an earlier generation, including his teacher Oskar Heinroth....
    ), 1985 (in German), ISBN 349200640X
  • A World of Propensities, 1990, ISBN 1855060000
  • The Lesson of this Century, Interviewer: Giancarlo Bosetti, English translation: Patrick Camiller), 1992, ISBN 0415129583
  • All life is Problem Solving, 1994, ISBN 0415249929
  • The Myth of the Framework: In Defence of Science and Rationality, (Edited by Mark Amadeus Notturno) 1994, ISBN 0415135559
  • Knowledge and the Mind-Body Problem: In Defence of Interaction, (Edited by Mark Amadeus Notturno) 1994 ISBN 0415115043
  • The World of Parmenides, Essays on the Presocratic Enlightenment, 1998, (Edited by Arne F. Petersen with the assistance of Jørgen Mejer), ISBN 0415173019
  • Frühe Schriften, 2006 (Edited by Troels Eggers Hansen, includes Popper's writings and publications from before the Logic, including his previously unpublished thesis, dissertation and journal articles published that relate to the Wiener Schulreform) ISBN 9783161476327
  • After 'The Open Society': Selected Social and Political Writings, 2008 (Edited by Jeremy Shearmur and Piers Norris Turner, it includes previously unpublished and uncollected essays), ISBN 0415309085


Further reading

  • [Comprehensive bibliography:] Lube, Manfred: Karl R. Popper. Bibliographie 1925–2004. Wissenschaftstheorie, Sozialphilosophie, Logik, Wahrscheinlichkeitstheorie, Naturwissenschaften. Frankfurt/Main etc.: Peter Lang, 2005. 576 pp. (Schriftenreihe der Karl Popper Foundation Klagenfurt.3.)
  • Stefano Gattei. Karl Popper's Philosophy of Science. 2009.
  • David Miller
    David Miller (philosopher)

    David W. Miller is a philosopher and prominent exponent of critical rationalism. He teaches in the Department of Philosophy at the University of Warwick in Coventry, United Kingdom....
    . Critical Rationalism: A Restatement and Defence. 1994.
  • David Miller
    David Miller (philosopher)

    David W. Miller is a philosopher and prominent exponent of critical rationalism. He teaches in the Department of Philosophy at the University of Warwick in Coventry, United Kingdom....
     (Ed.). Popper Selections.
  • John W. N. Watkins. Science and Skepticism. 1984.
  • Bailey, Richard, Education in the Open Society: Karl Popper and Schooling. Aldershot, UK: Ashgate 2000. The only book-length examination of Popper's relevance to education.
  • Bartley, William Warren III. Unfathomed Knowledge, Unmeasured Wealth. La Salle, IL: Open Court Press 1990. A look at Popper and his influence by one of his students.
  • Edmonds, D., Eidinow, J. Wittgenstein's Poker. New York: Ecco 2001. A review of the origin of the conflict between Popper and Ludwig Wittgenstein
    Ludwig Wittgenstein

    Ludwig Josef Johann Wittgenstein was an Austrian-United Kingdom philosopher who worked primarily in logic, the philosophy of mathematics, the philosophy of mind, and the philosophy of language....
    , focused on events leading up to their volatile first encounter at 1946 Cambridge meeting.
  • Feyerabend, Paul Against Method. London: New Left Books, 1975. A polemical, iconoclastic book by a former colleague of Popper's. Vigorously critical of Popper's rationalist view of science.
  • Hacohen, M. Karl Popper: The Formative Years, 1902 – 1945. Cambridge: Cambridge University Press, 2000.
  • Hickey, J. Thomas. Book V, Karl Popper And Falsificationist Criticism. www.philsci.com . 1995* Kadvany, John Imre Lakatos and the Guises of Reason. Durham and London: Duke University Press, 2001. ISBN 0-8223-2659-0. Explains how Imre Lakatos developed Popper's philosophy into a historicist and critical theory of scientific method.
  • Kuhn, Thomas S. The Structure of Scientific Revolutions. Chicago: University of Chicago Press, 1962. Central to contemporary philosophy of science is the debate between the followers of Kuhn and Popper on the nature of scientific enquiry. This is the book in which Kuhn's views received their classical statement.
  • Levinson, Paul
    Paul Levinson

    Paul Levinson is an United States author and professor of communications and media studies at Fordham University in New York City. Levinson's novels, short fiction, and non-fiction works have been translated into twelve languages....
    , ed. In Pursuit of Truth: Essays on the Philosophy of Karl Popper on the Occasion of his 80th Birthday. Atlantic Highlands, NJ: Humanities Press, 1982. A collection of essays on Popper's thought and legacy by a wide range of his followers. Includes an interview with Sir Ernst Gombrich
    Ernst Gombrich

    Sir Ernst Hans Josef Gombrich, Order of Merit, Order of the British Empire was an Austrian-born art historian who spent most of his working life in the United Kingdom....
    .
  • Magee, Bryan. Popper. London: Fontana, 1977. An elegant introductory text. Very readable, albeit rather uncritical of its subject, by a former Member of Parliament.
  • Magee, Bryan. Confessions of a Philosopher, Weidenfeld and Nicolson, 1997. Magee's philosophical autobiography, with a chapter on his relations with Popper. More critical of Popper than in the previous reference.
  • Munz, Peter. Beyond Wittgenstein's Poker: New Light on Popper and Wittgenstein Aldershot, Hampshire, UK: Ashgate, 2004. ISBN 0-7546-4016-7. Written by the only living student of both Wittgenstein and Popper, an eyewitness to the famous "poker" incident described above (Edmunds & Eidinow). Attempts to synthesize and reconcile the differences between these two philosophers.
  • Niemann, Hans-Joachim
    Hans-Joachim Niemann

    Hans Joachim Niemann, born in 1941 in Kiel on the Baltic Sea, is a German philosopher who has developed the methods of critical rationalism for applying them in the fields of metaphysics and ethics....
    . Lexikon des Kritischen Rationalismus, (Encyclopaedia of Critical Raionalism), Tübingen (Mohr Siebeck) 2004, ISBN 3-16-148395-2. More than a thousand headwords about critical rationalism, the most important arguments of K.R. Popper and H. Albert, quotations of the original wording. Edition for students in 2006, ISBN 3-16-149158-0.
  • Notturno, Mark Amadeus. "Objectivity, Rationality, and the Third Realm: Justification and the Grounds of Psychologism". Boston: Martinus Nijhoff, 1985.
  • Notturno, Mark Amadeus. On Popper. Wadsworth Philosophers Series. 2003. A very comprehensive book on Popper’s philosophy by an accomplished Popperian.
  • Notturno, Mark Amadeus. "Science and the Open Society". New York: CEU Press, 2000.
  • O'Hear, Anthony. Karl Popper. London: Routledge, 1980. A critical account of Popper's thought, viewed from the perspective of contemporary analytic philosophy.
  • Radnitzky, Gerard, Bartley, W. W., III eds. Evolutionary Epistemology, Rationality, and the Sociology of Knowledge. La Salle, IL: Open Court Press 1987. ISBN 0-8126-9039-7. A strong collection of essays by Popper, Campbell, Munz, Flew, et al, on Popper's epistemology and critical rationalism. Includes a particularly vigorous answer to Rorty's criticisms.
  • Richmond, Sheldon. Aesthetic Criteria: Gombrich and the Philosophies of Science of Popper and Polanyi. Rodopi, Amsterdam/Atlanta, 1994, 152 pp. ISBN 90-5183-618-X.
  • Schilpp, Paul A., ed. The Philosophy of Karl Popper, 2 vols. La Salle, IL: Open Court Press, 1974. One of the better contributions to the Library of Living Philosophers series. Contains Popper's intellectual autobiography, a comprehensive range of critical essays, and Popper's responses to them.
  • Schroeder-Heister, P. "Popper, Karl Raimund (1902–94)," International Encyclopedia of the Social & Behavioral Sciences
    International Encyclopedia of the Social & Behavioral Sciences

    The International Encyclopedia of the Social & Behavioral Sciences , edited by Neil J. Smelser andPaul B. Baltes, is a 26-volume work. It has some 4,000 signed articles, commissioned by around 50 subject editors, and includes biographical entries, 122,400 entries, and an extensive...
    , 2001, pp. 11727-11733.
  • Shearmur, Jeremy. The Political Thought of Karl Popper. London and New York: Routledge, 1996. Study of Popper's political thought by a former assistant of Popper's. Makes use of archive sources and studies the development of Popper's political thought and its inter-connections with his epistemology.
  • Stokes, G. Popper: Philosophy, Politics and Scientific Method. Cambridge: Polity Press, 1998. A very comprehensive, balanced study, which focuses largely on the social and political side of Popper's thought.
  • Stove, D.C.
    David Stove

    David Charles Stove , was an Australian philosophy of science.His work in philosophy of science included detailed criticisms of David Hume's inductive skepticism, as well as what he regarded as the irrationalism of his disciplinary contemporaries Karl Popper, Thomas Kuhn, Imre Lakatos, and Paul Feyerabend....
    , Popper and After
    Popper and After

    Popper and After is a book by David Stove first published by Pergamon Press in 1982. It was subtitled Four Modern Irrationalists. Popper and After has since been reprinted as Anything Goes: Origins of the Cult of Scientific Irrationalism and Scientific Irrationalism: Origins of a Postmodern Cult ....
    : Four Modern Irrationalists
    . Oxford: Pergamon. 1982. A vigorous attack, especially on Popper's restricting himself to deductive logic.
  • Thornton, Stephen. Stanford Encyclopedia of Philosophy
    Stanford Encyclopedia of Philosophy

    The Stanford Encyclopedia of Philosophy is a Open access online encyclopedia of philosophy maintained by Stanford University. The SEP was initially developed with U.S....
    ,
    2006.
  • Weimer, W., Palermo, D., eds. Cognition and the Symbolic Processes. Hillsdale, NJ: Lawrence Erlbaum Associates. 1982. See Hayek's essay, "The Sensory Order after 25 Years", and "Discussion".


External links

  • Documentary about Karl Popper on North German Broadcasting Cooperation Norddeutscher Rundfunk
    Norddeutscher Rundfunk

    Norddeutscher Rundfunk is a public broadcasting, based in Hamburg. In addition to the city-state of Hamburg, NDR transmits for the German states of Lower Saxony, Mecklenburg-Vorpommern and Schleswig-Holstein....
     (in German)
  • from
  • from
  • includes complete bibliography 1925–1999
  • International Association for the Promotion of Science and Research, in German
  • brief biography of Popper
  • George Soros foundations network
  • by Martin Gardner
    Martin Gardner

    Martin Gardner is a popular American mathematics and science writer specializing in recreational mathematics, but with interests encompassing magic , pseudoscience, literature , philosophy, scientific skepticism, and religion....
  • by J C Lester.
  • Site maintained by John Kadvany, PhD.
  • by Peter Singer
    Peter Singer

    Peter Albert David Singer is an Australian Philosophy. He is the Ira W. DeCamp Professor of Bioethics at Princeton University, and laureate professor at the Centre for Applied Philosophy and Public Ethics , University of Melbourne....
     The New York Review of Books, vol. 21, no. 7 (2 May 1974)
  • Persian translation by Khosro Naghed
    Khosro Naghed

    Khosro Naghed is a Iran scholar, Iranology and linguistics.He wrote numerous books and articles on Iranian culture, Persian history, Persian language and literature and philosophy....
  • , BBC Radio 4
    BBC Radio 4

    BBC Radio 4 is a domestic UK radio station that broadcasts a wide variety of spoken-word programmes, including news, drama, comedy, science and history....
     programme, In Our Time
    In Our Time (BBC Radio 4)

    In Our Time is a discussion programme hosted since 2002 by Melvyn Bragg on BBC Radio 4 in the United Kingdom, described as a series investigating the "history of ideas"....
    , 8 February 2007. Discussion with John Worrall, Professor of Philosophy of Science at the London School of Economics
    London School of Economics

    The London School of Economics and Political Science, more commonly referred to as The London School of Economics or LSE, is a specialist college of the University of London in London, England....
    , Anthony O'Hear, Weston Professor of Philosophy at Buckingham University
    University of Buckingham

    The University of Buckingham is the only degree awarding private university in the United Kingdom.Its two campuses are both located in Buckingham....
    , Nancy Cartwright, Professor of Philosophy at the LSE and the University of California
    University of California

    The University of California is a public university system in the U.S. state of California. Under the California Master Plan for Higher Education, the University of California is a part of the state's three-tier public higher education system, which also includes the California State University system and the California Community Colleges s...
    , hosted by Melvyn Bragg
    Melvyn Bragg

    Melvyn Bragg, Baron Bragg, Royal Society of Literature, Royal Television Society is a United Kingdom author and broadcaster....
    .
  • Site offers free downloads by chapter available for public use.
  • This is a microfilm copy of the Stanford University Popper Archive of Popper's papers to whose catalogue a weblink is provided.
  • (Karl Popper Archive at University Library Klagenfurt. Consists of Popper's Library and paper copies of the Popper Papers at The Hoover Institution Archive at Stanford, Cal.)
  • (Austrian Karl R. Popper Research Association - University of Graz, Austria)
  • from the .