Philosophy of Science: The Problem of Demarcation

Philosophy of Science: The Problem of Demarcation

Professor Jeffery Kasser produced a series of 36 lectures through The Great Courses entitled Philosophy of Science.

These are my notes, commentary, and synopsis from Kasser’s lectures.  The author of this blog highly recommends this course as a high quality lecture on the philosophy of science.

One may purchase the entire course here.

What makes science so special?  It seems to be special.  It makes extraordinary claims.  It usually speaks with authority in our courts and in all sections of government policy.  What is the basis of its power or prestige?  Does it deserve this prestige and power?

It seems that since science is so powerful and prestigious that we should have some criteria by which to define something as scientific.  There should be a procedure by which we can determine whether or not something is called science: we should be able to clearly determine what is included in science and what is excluded from science.  This is called the Problem of Demarcation.  Thus, we should define what is considered science and what we can call pseudo-science.

One may claim that a scientific claim is true, and that a pseudo-scientific claim is false.  One should be very careful with this claim, because upon close examination, it does not stand.  Science often makes claims that are false.  If the criterion for being scientific is falsifiability, then if one is to do science, some false predictions will happen, and are expected.  On the other hand, many pseudo-sciences often make true claims.  Astrology occasionally makes true claims with regard to your horoscope; some claims are false, but so are many scientific claims.  Thus, the truth or falsity of a claim cannot be the sole criteria of whether or not something is scientific.  If false claims are excluded from science, then we cannot get started with science by testing whether or not some claims are false in the first place.

Karl Popper made a useful contribution to the philosophy of science by attempting to define a core feature of a scientific claim, which was widely influential in his time and even today.  Popper wanted to distinguish what science was doing as opposed to that Freud, Marx, and Adler were doing; he considered the work they did as outside of the boundaries of science.  In their time, however, their work was widely considered scientific. 

One of Popper’s shocking assertions is that science is not special because of its conformance to observational evidence.  Pseudo-science uses plenty of evidence.  Astrology is a good example.  Observation is cheap: one can use observations to prove virtually anything.  Freud and Marx could make just about any evidence fit their theories.  This was a bad characteristic of their theories, according to Popper.  Evidence does not falsify pseudo-scientific claims.  Fitting data well is not is not the mark of a scientific theory. 

Einstein’s Theory of Relativity was a genuine scientific theory according to Popper.  Einstein’s theory made predictions.  These predictions were testable.  More importantly, these theories were falsifiable.  Einstein claimed that the sun’s gravitational field would bend light.  The theory survived a severe test after experiments observed this bold claim.

Popper claims that a scientific theory is falsifiable.  Science should make bold claims and then seek to falsify them.  Popper claimed that this is what scientists actually do and what they should do: this was an “is” and an “ought” proposition from Popper.  This, however, is not to be interpreted as a necessary condition; it is only a sufficient condition.  Not all falsifiable claims are scientific, but all scientific claims are falsifiable. 

Popper was not saying that people like Freud, Marx, and Adler did not say important things.  He was merely asserting that we cannot call their work scientific.  Popper even originally claimed that Darwin’s theory was pseudo-scientific, until later on when he changed his mind after a closer inspection of the theory.

Such a nice, straight-forward criteria for at least entry into the category of science sounds about right to many, but there are some problems with Popper’s approach.  Kasser’s example is a good illustration, “There is at least one gold sphere at least one mile in diameter in the universe.”  Such a claim does not appear to be falsifiable, but it does not appear to be unscientific either.  Statistical claims also appear unfalsifiable.  Kasser’s example is that a run of 50 sixes in a row does not falsify a claim that the die is fair.  Another problem is that if a theory is treated scientifically, is it science, or does the theory have to be stated scientifically?  It is also not clear if theories should be rejected simply because the theory does not conform to some observed results; the measuring instruments could have been defective, or the data may have been subject to fluctuations within the tolerance of the aforementioned statistical error. 

The virtue of Newton’s theory was that it explained a lot, not that it was falsifiable.  Thus, is it not clear that a theory is not scientific if it provides good explanations.  Perhaps if the data fits perfectly to the theory, the theory should be taken seriously in some cases.  Thus, Popper’s claim, while somewhat useful, is not air-tight, and in some cases, it appears not to offer any help in defining the necessary conditions of a scientific theory. 

Kasser claims that it is difficult to interpret falsifiability whereby physics passes the test and Freud does not.  Perhaps this is because in the process of doing physics, many ideas are falsified, and then reworked until they fit, as they would in Freud’s work and approach.  Kasser is not claiming that there is no difference between, say, Astrology and Physics; he is claiming that it is very difficult to see how Physics meets the falsifiability criteria while Astrology does not. 

In doing science, one cannot merely reject theories that have failed confirmation by evidence; if this were the case, science would stop.  A major task of science is reconciling the theory and the data: refining, regrouping, rearranging, and correcting failures of fit.  One must always be reminded that one cannot merely reject false theories as unscientific while asserting falsifiability criteria.  Popper stresses that science should make bold assertions and then seek to falsify them.  Thus, even false theories can be scientific, if they can be formatted according to the falsification criteria, according to Popper.  Such fields such as medicine tolerate a lot of false claims and theories due to its extreme complexity, but one can hardly claim that medical research is not scientific.

Other criteria have been proposed as solutions to the scientific Problem of Demarcation.  None look as hopeful as Popper’s criteria.  One proposal is that progress is a mark of science.  However, fields such as Chemistry have not progressed much in the last 50 years, while one may argue that Astrology has made progress with more data available on the position of the planets and the stars to aid in predictions for horoscopes.  Another proposal is that pseudo-science has no explanatory mechanism, while science does.  On the contrary, one must be reminded that one of the most successful scientific theories in history, Newton’s laws, posit the attraction of planets toward each other with some mysterious force called gravity that “reaches out” and “pulls” these large bodies together.  Newton does not attempt to explain the mechanism of gravity, but merely describes what happens with predictions that are more or less accurate.  Another proposal is that science is whatever a community of scientists says it is.  One must be reminded, however, that in the Soviet Union, there was a state-sponsored consensus on the truth of the biological theories of Lysenko, which is considered pseudo-science today.  There are proposals that pseudo-science is of dubious origin.  This does not work because almost all of science emerged from mythology or speculation; Alchemy preceded Chemistry.  A final illustrative proposal is that pseudo-science uses defective forms of reasoning in their theorizing.  If this is true, what of scientific theories that use reasoning by analogy, such as the gas laws which assume that gas molecules are little round balls?  Pseudo-science uses plenty of argument by analogy, and so does what is considered as real science. 

Kasser discusses an important debate in the court system which bears on the scientific Problem of Demarcation.  Forms of Creationism have not fared well within the US court system, where is has generally been declared to be pseudo-scientific.  However, as we have discussed above, there is no sure way of Demarcation in science, and all the arguments claiming that Creationism is pseudo-science can be applied to other legitimate branches of science.  It seems that the Problem of Demarcation has not been solved, and thus, calling something pseudo-science is problematic without this solution.

Kasser concludes with the claims that most philosophers do not think that the scientific Problem of Demarcation has received enough attention.  We cannot develop sure criteria for distinguishing between poor scientific theories and non-scientific theories.  If we do not address the Problem of Demarcation, we have no basis to declare that Astrology or Creationism as unscientific.  Furthermore, if we do not develop an adequate basis for scientific Demarcation, then declaring something as scientific is not much of an accomplishment.  For clarification, Kasser explains just because there are no criteria for scientific Demarcation does not mean that none can be formed. 

In conclusion, the scientific Problem of Demarcation is extremely difficult to formulate, and no criteria are satisfactory to date.  This presents problems because institutions must choose some criteria for scientific funding.  If there are no criteria for defining what is and is not science, how can we formulate acceptable criteria as to what is good science worthy of funding?  There are also legal and political consequences for this Demarcation problem since courts often decide what is good, bad or pseudo-science with regard to public policy on issues of public school curricula (creationism), environmental policy (pollution), regulations (smoking), medical funding, and health care, among other things.  Often, governments institute laws and regulations from the basis of scientific studies and scientific authority.  However, this study has illustrated that we cannot easily define what science is, much less why it is special and deserves such authority and recognition.

We often feel that science is special and deserves some authority and respect, but we have not gotten past its definition any further than, “I know it when I see it.”