Karl Popper: Critical Rationalism

KARL POPPER

Biography

Sir Karl Popper, in full Karl Raimund Popper born July 28, 1902, Vienna, Austria, died Sept. 17, 1994, Croydon, Greater London, Austrian-born British philosopher of natural and social science who subscribed to antideterminist metaphysics, believing that knowledge evolves from experience of the mind.

Philosophy  

Popper coined the term "critical rationalism" to describe his philosophy. Concerning the method of science, the term indicates his rejection of classical empiricism, and the classical 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 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 also wrote extensively against the famous Copenhagen interpretation of quantum mechanics. He strongly disagreed with Niels Bohr's instrumentalism and supported Albert Einstein's realist approach to scientific theories about the universe. Popper's falsifiability resembles Charles Peirce's nineteenth century fallibilism. In Of Clocks and Clouds, Popper remarked that he wished he had known of Peirce's work earlier.

Critical rationalism  is  an epistemological philosophy Popper's approach in this philosophy is based on the naturalistic idea that society has developed through a process of solving problems using trial and error. The natural and social sciences have been born out of such problem solving and progressed by subjecting potential theories to vigorous testing and criticism. Falsified theories are rejected. Popper calls for a society which is conducive to such problem solving, a society which permits bold theorizing followed by unfettered criticism, a society in which there is a genuine possibility of change in the light of criticism: an open society. Popper's ideas provide a doorway for accessing philosophical ideas and debates relevant to OR. For some such as Boothroyd it has proved inspirational, for others such as Ulrich it has provided a critical point of departure.

If I choose one on his many philosophies, I choose his philosophy of science, falsification problem induction to be exact. Among his contributions to philosophy is his claim to have solved the philosophical problem of induction. He states that while there is no way to prove that the sun will rise, it is possible to formulate the theory that every day the sun will rise; if it does not rise on some particular day, the theory will be falsified and will have to be replaced by a different one. Until that day, there is no need to reject the assumption that the theory is true. Nor is it rational according to Popper to make instead the more complex assumption that the sun will rise until a given day, but will stop doing so the day after, or similar statements with additional conditions. Such a theory would be true with higher probability, because it cannot be attacked so easily: to falsify the first one, it is sufficient to find that the sun has stopped rising; to falsify the second one, one additionally needs the assumption that the given day has not yet been reached. Popper held that it is the least likely, or most easily falsifiable, or simplest theory that explains known facts that one should rationally prefer. His opposition to positivism, which held that it is the theory most likely to be true that one should prefer, here becomes very apparent. It is impossible, Popper argues, to ensure a theory to be true; it is more important that its falsity can be detected as easily as possible. Popper and David Hume agreed that there is often a psychological belief that the sun will rise tomorrow, but both denied that there is logical justification for the supposition that it will, simply because it always has in the past. Popper writes, "I approached the problem of induction through Hume. Hume, I felt, was perfectly right in pointing out that induction cannot be logically justified." 

Opinion

In my opinion, Popper always falsify things, he always see that there is a possibility that a thought can have a false information, but he states that there will always be a replacement if one thing is missing. For me Popper is  a great philosopher because, he is known for his vigorous defense of liberal democracy and the principles of social criticism that he came to believe made a flourishing open society possible.