A2 Karl Popper Extended Version
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Karl Popper proposed that scientific knowledge is provisional and falsifiable rather than absolutely certain or proven true. He rejected the traditional view that science discovers descriptive laws through induction from facts. Instead, he argued that scientific theories can never be proven true but can be tested by attempting to falsify them through experiments and observations. This view resolved issues with the logical problem of induction and provided a rationale for how scientific knowledge advances through falsification of theories.
A2 Karl Popper Extended Version
- 1. Karl Popper Quote: “ All knowledge is provisional, temporary, capable of refutation at any moment”
- 3. The nature and status of sociological research has always been an area of controversy. Thus it makes sense to understand a little about the nature of the scientific method, because until we can grasp the nature of science we cannot hope to understand how, or whether, sociology fits into it. Introduction
- 4. Why Popper? Since we have to make comparisons we need to know to what it is that sociology is being compared. A good starting point is the work of Karl Popper, particularly since he debunks many of the cherished common sense beliefs concerning the logic of scientific inquiry.
- 5. Background Karl Popper was a philosopher of science. Sir Peter Medawar, a winner of the Nobel Prize for Medicine, said on BBC Radio 3 on 28/7/72: 'I think Popper is incomparably the greatest philosopher of science that has ever been.' Popper's view of science is of great value to us in forming some coherent idea of what science is and of how it advances our knowledge. The most important point to grasp is that Popper held a view of science that is quite different to the traditional or 'common sense' view.
- 6. The Traditional View of Science Science uncovers descriptive laws . These are quite different to social laws , which are prescriptive . Social laws tell citizens what they can or cannot do, and clearly they can be broken. A law of nature is not prescriptive but descriptive - it tells us what happens. Such a law may be true or false but it cannot be broken because it is not a command. Scientific statements based on experimental and observational evidence (facts) were contrasted with statements of other kinds, whether based on authority, emotion, tradition, speculation, prejudice or habit.
- 7. Questioning the Standard of Science Questions about the approach laid out above have been asked for a very long time. The philosopher David Hume questioned induction , the very basis of the scientific method. He pointed out that no number of singular observation statements, however large, could logically entail an unrestricted general statement. For example, the fact that the laws of physics have been found to hold good in the past does not logically entail that they will continue to hold true in the future. The whole of traditional science assumed the regularity of nature - assumes that the future will be like the past.
- 8. Observing Past & Its Bearing on the Future? It cannot be established by observation since we cannot observe future events. It cannot be established by logical argument since, as Popper argues: 'From the fact that all past futures have resembled past pasts it does not follow that all future futures will resemble future pasts.' This means that scientific laws have no rationally secure foundation in logic, or experience. Although as Hume came to believe, we may be so constituted psychologically that we cannot help thinking in terms of them.
- 9. Hume Concluded What Hume had shown was that pure empiricism was not a sufficient basis for science. Bertrand Russell simply argued that if the principle of induction was admitted (allowed) everything else can proceed in accordance with the theory that all our knowledge is based on experience.
- 10. Popper's Solution Popper offers an acceptable solution to the problem of induction. He rejects the orthodox view of science and replaces it with another. His argument points to the logical asymmetry between verification and falsification. What it comes down to, is that we may never be able to prove a theory true (because of the problem of induction), but we can prove a theory false.
- 11. Falsifiable? In this important logical sense, empirical generalisations though not verifiable are falsifiable. This means that scientific laws are testable in spite if being unprovable ; they can be tested by systematic efforts to refute them. Refutation adds to our knowledge, to know that a theory is wrong is to know more than not to be aware that a theory is wrong.
- 12. Popper's Contribution Popper also provides a further example of why pure empiricism is insufficient for scientific advance. Most of the great scientific revolutions have turned on theories of creative imagination and insight. science is not just about the observable - science reveals an unseen world of forces, waves, cells and particles.
- 13. The popular notion that the sciences are bodies of established fact is entirely mistaken. Nothing in science is permanently established, nothing unalterable. Thus...
- 14. What Science does based on 'truth' What scientists do is base decisions and expectations on the best of our knowledge and provisionally assume the 'truth' of that knowledge for practical purposes, because it is the least insecure foundation available.
- 15. Popper's theory is... an account of the logic and history of science and not of the psychology of its practitioners. not under the impression that scientists in general have regarded themselves as doing what he describes. Saying that whether they realise it or not, this is the rationale of what they do , and accounts for the way human knowledge develops .
- 16. Marxism Example Marxism says there will be a revolution leading to a classless society. Has not happened yet due to a false consciousness of the proletariat. Thus, the prediction cannot be falsified. If there is a revolution, then Marxism is correct, and if not, Marxism is still correct.
- 17. Popper and Scientific Sociology Says it is possible for sociology to be scientific since it can produce hypotheses that can be falsifiable. Despite Popper’s rejection of Marxism as unscientific because it is untestable, he does not believe that untestable ideas are worthless. Such ideas may be of value as they may become testable at a later time, and can use them for clarity of other topics and logical consistency.
- 18. Julienne Ford (1969) Said that comprehensive schooling would produce social mixing of pupils from different social classes. She was able to test and falsify this hypothesis through her empirical research.
- 19. Popper Argues the Following... That every discovery contains an irrational element, or a creative intuition. Einstein in a letter to Popper states quite explicitly his agreement with Popper that theory cannot be fabricated out of the results of observation, but that it can only be invented . Observation as such cannot be prior to theory since theory is presupposed by any observation. Failure to recognise this is, in Popper's view, is a flaw in the foundation of the empirical tradition.
- 20. Furthermore... The belief that science proceeds from observation to theory is very widely held, but the belief that we can start with pure observation, without anything in the nature of theory, is absurd. Observation is always selective. It needs a chosen object, a definite task, an interest, a point of view, a problem. Observations are interpretations in the light of theories.
- 21. Criticisms However, there are serious objections to falsification. The history of science throws up many examples of falsifying evidence that has been rejected. Chalmers (1982) points out that if falsification had been strictly adhered to both Newton's gravitational theory and Bohr's theory of the atom would have been falsified earlier than they were.
- 22. Next Up… Thomas Kuhn