I. Background

A. Popper: extremely influential philosopher and intellectual of the mid-20th century. One biographer writes:

“Karl Popper is generally regarded as one of the greatest philosophers of science of the 20th century. He was also a social and political philosopher of considerable stature, a self-professed ‘critical-rationalist’, a dedicated opponent of all forms of scepticism, conventionalism, and relativism in science and in human affairs generally, a committed advocate and staunch defender of the ‘Open Society’, and an implacable critic of totalitarianism in all of its forms. One of the many remarkable features of Popper's thought is the scope of his intellectual influence. In the modern technological and highly-specialised world scientists are rarely aware of the work of philosophers; it is virtually unprecedented to find them queuing up, as they have done in Popper's case, to testify to the enormously practical beneficial impact which that philosophical work has had upon their own.”

 

B. The essay on reserve presents one of the views for which he is most well known. It is an extremely influential essay. It is often cited in discussions of the nature of science. It comes up a lot in discussions of evolution and intelligent design. Standard idea: intelligent design is not science because it is not falsifiable. Describe results of web search.

 

C. In the text, Rosenberg connects this to the problems of induction. For now, this will be our emphasis. But it will be helpful get some grasp of Popper’s answer to the “What is science?” question. On p. 38, Popper formulates his question. Note: it is not about when a theory is true or reasonable. It is about when it counts as science at all. More specifically, it is: when does something count as science rather than pseudoscience? This has come to be known as “the demarcation problem.”

 

D. He gives examples that are supposed to illustrate the distinction he wants to discuss. Popper identifies the following:

Science: Einstein’s theory of relativity.
Pseudoscience: astrology; Marx, Freud, Adler.

Maybe it would be good to say a little about what these allegedly bad theories say. What follows are gross over-simplifications.

Adler: “Adler's "individual psychology" focused on the efforts people invariably make in order to compensate for their (self-perceived) inferiority to others, whether it originally arose from a specific physical defect, relative position in the family constellation, particular experiences of humiliation, or a general lack of social feeling for others.” So human behavior will be explained in terms of these feelings and our ways of coping with them. See p. 40.

Marx: “Marx argued that the conditions of modern industrial societies invariably result in the estrangement (or alienation) of workers from their own labor.” Argued that capitalism was doomed to fail, that workers would eventually seize control from the owners, and a classless society would result. So social-historical events will be explained in terms of these kinds of considerations. See p. 40 for Popper’s example of this.

Freud: too hard to summarize his many ideas. But key here is the idea that early experiences, particularly having to do with sexual development, are crucial to determining adult behavior. Psychoanalysis can help to recover lost memories and correct the behavior.

See example at very bottom of p. 40.

 

II. Falsifiabilty

 

Comments refer to passages on handout distributed in class.

 

A. Popper’s View

 

Quote 1) If you thought induction was the key to understanding science, you’d have no good solution to the demarcation problem. There are lots of positive instances of the pseudoscience theories.

Instead, he thinks, the key idea is falsifiability. We don’t have to solve the problem of induction. In fact, he says, we don’t even make inductions! So once we get straight on the method, we escape both the problem of induction and solve the demarcation problem.

 

2) We just saw why he says (a). (b) - He thinks that observations and experiments are used just to refute, not to confirm, theories. (c) - Not too much is said here about this. But you should be able to see why he’d say this, given what has already been said.

 

3) These do look like they form an inconsistent set of propositions.

 

4) Notice the two parts of this claim.

 

B. Rosenberg’s Discussion of Popper

 

Quote 1) Pseudo-problems . Not: something that only seems to be a problem but isn’t one because the answer is easy or obvious. Rather: we only thought it was a problem because of some confusion on our part. It is often said that the problem gets “dissolved” rather than “resolved.” A possible example: suppose you got yourself all in a frenzy searching for the average American, and not finding him/her anywhere, started making up alternative places where the person is. And people argued about this. It’s just a confusion.

 

But: induction is not exactly like this. It’s not a confusion to ask whether inductive inferences are justified. Instead, Popper thinks we don’t use it and don’t need it. So it’s not a problem that we have to worry about. Cf.(?), how come the wires for electric cars don’t cause lots of problems? They don’t have wires, but they would be real problems if they did use them.

 

2) (a) is for the reasons we’ve already discussed. The emphasis is on “completely.” Note that if (2c) from Popper is right, they are not even partly confirmed. (b) corresponds to Popper’s claim (4).

 

3) This may seem very confusing. Doesn’t it conflict with (2)?

 

On the one hand, there seems to be a real asymmetry - we can disprove things, but not prove them. Contrast “All observed As are Bs, so all As are Bs” (bad) and “This A is not a B, so not all As are Bs” (good). If we can observe positive instances, then we can also observe negative instances. But the latter falsify, the former do not prove. Yet R. seems to say that there’s a problem with the latter argument also. What’s the problem?

 

The problem with the bad argument is “logical” - (allegedly) the conclusion does not follow from the premise. The problem with falsification is that there is doubt about the premise. Go over R’s example about copper. This is where the “auxiliary assumptions” come inthat R. mentions in the paragraph from which quote 3 is taken.

 

C. Some Puzzles about Falsification

 

1) [The following point was messed up in class today.]For the same reasons that “All As are Bs” can’t be proved “There are As.” cannot be falsified. You can search the world all you like and never turn up an A. But to conclude “There are no As” would require induction. No experience can disprove “There are As.” If any such statements count as good science, that seems bad for Popper. But maybe they aren’t science. Similar considerations apply to more complex sentences such as “For every A, there is a B that stands in relation R to A.” You can find lots of positive instances. But to falsify this you would have to find an A for which there is no B. But it’s hard to see how you can observe that there is no B. (Maybe what R is will matter.) Again, if such statements count as part of science, it seems bad for Popper.

 

2) Rejecting induction as Popper does is surely extreme. If, as a simplistic interpretation of Popper seems to suggest, he thought that Hume was right, then this is not just a conclusion about scientific methodology. It also applies to ordinary life. Are we to say that we don’t have good reasons to believe ordinary things based on experience, e.g., my light will go off when I flip the switch, that getting hit by the oncoming bus will hurt, etc?

 

3) Notice the conclusion R. - quote 4 - draws from the example about copper: it is not that there is no important “logical” difference between falsifying something and proving it by induction. Rather, the conclusion is a point about the behavior of some people. This is a major shift in the topic. We were supposed to be finding an answer to the demarcation problem - what makes a theory or statement scientific - and instead we got an account of a difference in the behavior of people.

 

4) In the light of (3), notice that seemingly good scientists take advantage of the possibility of denying auxiliary assumptions. Recent study about low fat diets and health. Describe reactions. The difference between the good use of denying auxiliary assumptions and the bad use is not so clear. So started out seeming to be a clear distinction - science v. non-science - has gotten much messier.