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Karl Popper -
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Consequences of Popper's theses


Popper's logic


Karl Popper expressed his views about hypotheses in his book "The Logic of Scientific Discovery".

He claimed that verifications do not exist and that knowledge, which he equals with science, consists of arbitrary statements that should be possible to falsify.

As falsification of a statement is logically equivalent to verification of the negation of the statement, Popper's argumentation is obviously logically erroneous.


Both verification, which Popper denies, and falsification are founded on verification.

In spite of logical errors, arguments may still be interesting when compared to our perceived reality.

If, on the other hand, a logically erroneous argumentation leads to absurd consequences, one must conclude that the content is not that interesting.


Popper: A falsified fantasy is scientific


An arbitrary statement is, according to the criteria of Popper, scientific if it is falsifiable.

A reasonable proposition is that details in stories told by fiction writers are possible to falsify, not the least when the author him or herself has stated that the story is imagined.

Stories created by fiction writers are hence scientific according to the definition by Popper.

Lord of the Rings

Should the epic novel Lord of the Rings by JRR Tolkien according to Popper's theses be regarded as scientific?

It is quite clear that details in the story are falsifiable - Tolkien himself has claimed that he made them up.

Hence the story is, according to Popper, scientific.

Image: Wikipedia

Stories of creation

Within many religions there can be found a story of creation with the purpose to explain how man was created. For example the Jewish-Christian-Muslim and Norse religions claim that man was created directly through intervention of gods.

A vast number of observations and DNA sequences very strongly indicate that animals and plants have developed through evolution.

If we believe in evolution we can conclude that for example the story about Adam and Eve in the Paradise is incorrect. It is falsified.

According to Popper's theories, where falsifiability is claimed to define whether a statement is scientific or not, this implies that the Jewish-Christian-Muslim and Norse religious stories of creation today should be regarded as scientific evidence.



Within astrology, it is claimed that the positions of stars and planets at the moment of birth, influence our personal character. Is this a scientific claim?

Popper claimed that astrology is not a scientific area:

Astrology did not pass the test. Astrologers were greatly impressed, and misled, by what they believed to be confirming evidence - so much so that they were quite unimpressed by any unfavorable evidence.

Popper (1985) - Conjectures and
, 4Ed, p.37.

Scientific studies of astrology

We can perform an analysis of the Swedish population using id-numbers which reveal day of birth. The occupations of the population can also be analyzed from taxation data. Time of birth and occupations may then be tested against planet positions.

An example of statistical testing of astrological claims can be found in the book Gauquelin (1972) - Astrology and Science, s.132. The book may provide inspiration for possibilities for scientific methods within astrology.

Many details within astrology may hence be shown to be erroneous. As they are falsifiable, they should, according to the theories of Popper, be regarded as scientific.


Will a falsified hypothesis become non-scientific?


An attempt to save Popper's theses from the total breakdown described above, is that an according to Popper "scientific hypothesis" (i.e. falsifiable) should be altered to a "non-scientific hypothesis" in case it is actually falsified.

This is called "sophisticated falsification" (!) and have been suggested e.g. in Chalmers - What is this thing called Science? p.74. Sophisticated falsification is also said to imply that a falsifiable statement may be replaced by a statement that is easier to falsify.


"Sophisticated falsification" is possible to express like if Popper had said:

I don´t know if a hypothesis represents science or not - I wait and see until the hypothesis, or the consequences from it, has been verified or falsified enough until I make my judgment.

Such a remark represents the sceptical position that is characteristic for the "scientific method".