1) Karl Popper

• Sir K____ P____ (1902-94) was probably the most influential p____ of s___ of the 20th century. His ideas about science have important implications for sociology.

• Popper notes that many systems of thought claim to have true knowledge about the world, such as what

• Sir Karl Popper (1902-94) was probably the most influential philosopher of science of the 20th century. His ideas about science have important implications for sociology.

• Popper notes that many systems of thought claim to have true knowledge about the world, such as religions, political ideologies, tradition, intuition and common sense, as well as science.

Popper sets out to answer two related questions about science- what are they ?

, Popper sets out to answer two related questions about science:

1. What is it that distinguishes scientific knowledge from other forms of knowledge - what makes scentific knowledge unique?

2. Why has scientific knowledge been able to grow so spectacularly in just a few centuries?

The fallacy of induction

• In Popper's view, the main reason why we should reject verificationism is what he calls 'the fallacy [error) of induction'. - The fallacy of induction is the mistake of assuming that a theory can be proven true just because many observations support it.

• As we have seen, induction is the process of moving from the observation of particular instances of something to arrive at a general statement or law.

To illustrate the fallacy of induction, Popper uses the example of swans:

• For example, if we observe many white swans, we might conclude that “all swans are white.” However, no matter how many white swans we see, this cannot guarantee the statement is true—a single black swan would disprove it.

• Popper used this example to show that we cannot verify a theory simply by collecting supporting observations, which is why he rejected the positivist view that the distinctive feature of science lies in inductive reasoning and verificationism.

The fallacy of induction

• In Popper's view, the main reason why we should reject verificationism is what he calls 'the fallacy [e____) of induction'. - what is the definition of the fallacy of induction

• As we have seen, induction is the process of what

To illustrate the fallacy of induction, Popper uses the example of swans- explain his example

• Popper used this example to show that we cannot verify a theory simply doing what , which is why he rejected the positivist view that the distinctive feature of science lies in i____ r____ and v____.

Falsificationism

• In Popper's view, what makes science a unique form of knowledge is the very o____ of v____ - a principle he calls falsificationism.

• Falsification is the idea that what?

• That is, we must be able to say what e____ would count as f_____ the statement when we come to put it to the test. For example, a test would disprove the law of gravity if, when we let go of an object, what happened ?

For Popper, a good theory has two features:

• It is in principle f____ but when tested, stands up to all a____ to d___ it.

• It is bold - that is, it claims to explain a great deal. It makes b____ g____ that precisely predict a large number of cases or events, and so is at greater risk of being falsified than a more t____ theory that only tries to explain a s____ number of events.

Falsificationism

• In Popper's view, what makes science a unique form of knowledge is the very opposite of verificationism - a principle he calls falsificationism.

• Falsification is the idea that a scientific statement is one that is capable of being falsified - proved wrong - by the evidence.

• That is, we must be able to say what evidence would count as falsifying the statement when we come to put it to the test. For example, a test would disprove the law of gravity if, when we let go of an object, it did not fall.

For Popper, a good theory has two features:

• It is in principle falsifiable but when tested, stands up to all attempts to disprove it.

• It is bold - that is, it claims to explain a great deal. It makes big generalisations that precisely predict a large number of cases or events, and so is at greater risk of being falsified than a more timid theory that only tries to explain a small number of events.

Truth

• For Popper (1965), 'all knowledge is p_____, t____, capable of refutation at any moment' - there can never be absolute proof that what?

• This is because, as the renowned physicist S____ H____ (1988) puts it:

‘No matter how many times the results of e___ a____ with some theory, you can never be sure that the next time the r____ will not c_____ the theory.

• A good theory isn't necessarily a t_____ theory, therefore - it is simply one that has withstood attempts to f___ it s___ f___.

Truth

• For Popper (1965), 'all knowledge is provisional, temporary, capable of refutation at any moment' - there can never be absolute proof that any knowledge is true.

• This is because, as the renowned physicist Stephen Hawking (1988) puts it:

‘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.

• A good theory isn't necessarily a true theory, therefore - it is simply one that has withstood attempts to falsify it so far.

Criticism and the open society

• For a theory to be falsifiable, it must be open to what ?

• In Popper's view, therefore, science is essentially a p_____ a____ . He sees the scientific community as a h___ environment in which everything is open to c____, so that the f___ in a theory can be r____ e___ and b___ theories developed. Popper believes that this explains why scientific knowledge grows so r____.

• Popper argues that science thrives in 'open' or liberal societies - ones that believe in free expression and the right to challenge accepted ideas.

• By contrast, 'closed' societies are dominated by an official belief system that claims to have the absolute truth - whether a religion, or a political ideology such as Marxism or Nazism. Such belief systems stifle the growth of science because they conflict with the provisional, falsifiable nature of scientific knowledge.

• For example, the 17th century astronomer Galileo was punished by the church Rome for claiming that the Earth revolved around the Sun, showing how a closed society can suppress scientific idea

Criticism and the open society

• For a theory to be falsifiable, it must be open to criticism from other scientists.

• In Popper's view, therefore, science is essentially a public activity. He sees the scientific community as a hothouse environment in which everything is open to criticism, so that the flaws in a theory can be readily exposed and better theories developed. Popper believes that this explains why scientific knowledge grows so rapidly.

• Popper argues that science thrives in what type of societies - ones that believe in f____ e___ and the right to c____ accepted ideas.

• By contrast, 'c___' societies are dominated by what that claims to be what?- whether a r___, or a p____ i____ such as M___ or N__. how do such belief systems stifle the growth of science

• For example, the 17th century astronomer Galileo was punished by the church Rome for claiming what, showing how a c____ society can suppress scientific idea

Implications for sociology

• Popper believes that much sociology is unscientific because it consists what ?

• For example, Marxism predicts that there will be a what , but that it has not yet happened because of what???

• Hence the p____ cannot be falsified. If there is a r____, Marxism is correct - and if there isn't a r___, Marxism is still correct.

• Although Popper sees Marxism as u____ because it is u____, he believes untestable ideas can still be v____.

• They may become t____ later, and they help clarify t___, challenge a____, and generate what

• why does Sociology has more untestable ideas than the natural sciences ?

Implications for sociology

• Popper believes that much sociology is unscientific because it consists of theories that cannot be put to the test with the possibility that they might be falsified.

• For example, Marxism predicts that there will be a revolution leading to a classless society, but that it has not yet happened because of the false consciousness of the proletariat.

• Hence the prediction cannot be falsified. If there is a revolution, Marxism is correct - and if there isn't a revolution, Marxism is still correct.

• Although Popper sees Marxism as unscientific because it is untestable, he believes untestable ideas can still be valuable.

• They may become testable later, and they help clarify thinking, challenge assumptions, and generate testable hypotheses.

• Sociology simply has more untestable ideas than the natural sciences and this may simply be because it has not been in existence as long as they have.

Implications for sociology

• However, Popper believes that sociology can be s____

• , because it is capable of producing h____ that can in principle be falsified. For example, J____ F____ (1969) hypothesised that what

• She was able to test and falsify this hypothesis through what

Implications for sociology

• However, Popper believes that sociology can be scientific

• , because it is capable of producing hypotheses that can in principle be falsified. For example, Julienne Ford (1969) hypothesised 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.