Karl Popper Biography Quotes 13 Report mistakes

Early Life and Education
Karl Raimund Popper was born on 28 July 1902 in Vienna, then part of Austria-Hungary, into a cultivated family of Jewish origin that had converted to Lutheranism. His father, Simon Siegmund Carl Popper, was a lawyer and an erudite bibliophile, and his mother, Jenny Schiff, fostered his early love of music and culture. Vienna in his youth was a crucible of artistic and intellectual ferment, and Popper absorbed its tensions between tradition and radical change. As a young man he briefly flirted with Marxist ideas but rejected them after reflecting on their dogmatic tendencies and on the dangers of political violence. He enrolled at the University of Vienna, where he studied a range of subjects and completed a doctoral dissertation in psychology in 1928. In this period he encountered ideas associated with Karl Buhler's circle in Vienna as well as debates in logic and scientific method that would shape his philosophical outlook. In 1930 he married Josefine Anna (Hennie) Henninger, who became his lifelong companion and intellectual supporter.

Vienna and the Birth of Falsificationism
During the early 1930s Popper taught in schools while writing on the logic of science. He was in contact with members of the Vienna Circle, including Moritz Schlick, Rudolf Carnap, Otto Neurath, and Hans Hahn, though he was not a member and often disagreed with their verificationist program. His first major book, Logik der Forschung (1934), later translated as The Logic of Scientific Discovery, advanced a new answer to the demarcation problem: scientific theories are distinguished not by verification but by falsifiability, their openness to being refuted by conceivable tests. He drew inspiration from the testable boldness of Albert Einstein's theories, contrasting them with systems he regarded as unfalsifiable, such as certain interpretations of Marxism and psychoanalysis. He also engaged with Alfred Tarski's account of truth as correspondence, which helped him defend a realist view of knowledge while still insisting that all knowledge remains fallible and conjectural.

Exile in New Zealand and Political Thought
The rise of Nazism and the dangers it posed to people of Jewish ancestry convinced Popper to leave Austria. In 1937 he accepted a position at Canterbury University College (now the University of Canterbury) in Christchurch, New Zealand. There he developed his philosophy of critical rationalism and turned with urgency to political philosophy. During the war years he wrote The Poverty of Historicism (first published in the mid-1940s in articles, later as a book) and The Open Society and Its Enemies (1945). These works criticized historicism, the belief that history unfolds according to discoverable laws, and attacked the totalitarian tendencies Popper saw in interpretations of Plato, Hegel, and Marx. He argued for piecemeal social engineering, institutional checks, and a politics centered on learning from error. In New Zealand he formed important intellectual connections, notably with Friedrich A. Hayek, whose own defense of liberal institutions resonated with Popper's emphasis on open criticism and dispersed knowledge.

London School of Economics and Mature Philosophy
After the war, with Hayek's support, Popper moved to the London School of Economics in 1946, first as Reader in Logic and Scientific Method and later as Professor. At the LSE he refined the logic of conjecture and refutation, proposed the propensity interpretation of probability to make sense of single-case chances in science, and developed a sustained defense of realism. His essays were collected in Conjectures and Refutations (1963), which emphasized that knowledge grows through bold hypotheses and severe tests, not through accumulation of positive instances. In Objective Knowledge (1972) he articulated his three-worlds framework: the physical world (World 1), subjective mental states (World 2), and the objective contents of thought such as theories and problems (World 3). He also pursued critical discussions of quantum theory and determinism, material later assembled in volumes such as Realism and the Aim of Science and other works derived from his Postscript to The Logic of Scientific Discovery.

Debates, Students, and Collaborations
Popper's career intersected with many of the century's major thinkers. The contested 1946 encounter with Ludwig Wittgenstein at the Cambridge Moral Sciences Club, with Bertrand Russell present, highlighted deep differences over the role of problems and examples in philosophy. With Alfred Tarski he shared a realism about truth that set them against more verificationist outlooks. He maintained a lifelong admiration for David Hume's challenge to induction and sought to resolve it by replacing justification with critical testing. Among those influenced by him were Imre Lakatos, who developed a methodology of scientific research programs; W. W. Bartley, a defender of pancritical rationalism; Joseph Agassi; J. W. N. Watkins; David Miller; and, more ambivalently, Paul Feyerabend, who began close to Popper's views before advancing a more radical pluralism. Popper debated Thomas S. Kuhn on the nature of scientific change, arguing that even during periods of normal science, criticism and testing remain crucial. He also collaborated with the neuroscientist John C. Eccles on The Self and Its Brain (1977), where they explored the relationship between consciousness and the brain and further elaborated the three-worlds scheme. Biologists such as Peter Medawar praised Popper's account of conjecture and refutation as capturing the working spirit of laboratory science.

Honors, Later Years, and Legacy
Popper was knighted in 1965 for his services to philosophy, and he continued to lecture and write after retiring from the LSE in 1969. His intellectual autobiography, Unended Quest (1976), reflects both his personal history and his conviction that learning proceeds through the correction of error. He remained active in public debate, defending liberal institutions and criticizing doctrines that, in his view, insulated themselves from empirical challenge. His later philosophical output included further elaborations of realism, fallibilism, and the autonomy of World 3, as well as continued discussions of probability and quantum theory. Hennie Popper's unwavering support was integral to his work; she predeceased him after decades of partnership. Karl Popper died in 1994 in England.

Popper's legacy spans the philosophy of science, political theory, and the practice of many disciplines that prize rigorous testing and open criticism. He reshaped the demarcation problem, formalized critical rationalism as a way of life, and urged scholars and citizens alike to prefer institutions that make it easy to detect and correct mistakes. By insisting that progress rests on the willingness to submit our best ideas to severe scrutiny, he provided a framework that continues to influence scientists, economists, and philosophers long after his passing.

Our collection contains 13 quotes who is written by Karl, under the main topics: Ethics & Morality - Wisdom - Deep - Freedom - Free Will & Fate.

Other people realated to Karl: Theodor Adorno (Philosopher), Friedrich August von Hayek (Economist), George Soros (Businessman)