AF Chalmers - What is this thing called Science?

Chapter 7 - The limitations of falsificationism



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Chapter 7 - The limitations of falsificationism



The generalizations that constitute scientific laws can never be logically deduced from a finite set of observable facts, whereas the falsity of a law can be logically deduced from a single observable fact with which it clashes.

Nothing in our perceived reality can be logically deduced, which is also true for a scientific hypothesis that has been confirmed to such an extent that it is called a “law”.

Falsification of a hypothesis may decrease our confidence in it. See comment to p.83 and 59.

An observation is more reliable than a hypothesis. Observations generalized by induction are more reliable than a single observation (see comment to p.84) but no observation represents “absolute certain knowledge”.

Because an observation does not represent “absolute certain knowledge”, a deduction from it cannot be said to represent such “knowledge” either.


Straightforward, conclusive falsifications of theories by observation are not achievable.

Here Chalmers claims what was said in the comment above, but he seems not to understand it.


Falsificationism inadequate on historical grounds
Chalmers tells some examples where theories during their development seems to have been falsified

The common warning in believing that Chalmers’ stories represent some historical consensus is repeated.

Within science one single observation is rarely sufficient to demonstrate something in our perceived reality, i.e. only a single verification or a single falsification of a hypothesis is most often judged as inadequate for a change of its acceptance.


The Copernican Revolution

The “revolution” which is most often called the “scientific revolution” was a gradual change in attitudes from dogmatic to scientific that took place during about 100 years.


Copernicus published details about a heliocentric planet system 1543.

This gave a major theory change.

The change was a change in beliefs from a geocentric to a heliocentric planet system.

The basis for Copernicus’ arguments consisted of observations that were summarized into hypotheses that in turn were expressed mathematically.


The details of the story of this theory change do not lend support to the methodologies advocated by the inductivists and falsificationists.

As commented to p.83, induction and falsification are different types of methods.  A comparison between verification and falsification is more relevant.

Had Copernicus not known that planets existed, he could not form hypotheses about planetary orbits. Observations of planets hence were a prerequisite for his hypotheses. See also comments to p.12, 13, 69 and 70.

In case somebody saw a planet in the sky once, he might have believed that it was yet another star. No recordings of orbits nor that several planets existed would have been reported. But when several observations of moving planets were gathered, concepts like existence of something odd in the sky, and later the orbits of these odd objects, began to form. A belief in planets hence grew through induction from several observations to a general concept.

Observations of planets and induction were hence prerequisite for Copernicus’ hypotheses. The details of the story hence lend support to a scientific investigation method.

History does not lend support to falsificationism.

Copernicus’ arguments could obviously neither be verified nor falsified to an accepted level at the time they were published.


The person who contributed most significantly to the defense of the Copernican system was Galileo.

Galileo Galilei verified the Copernican system through observations which added to the acceptance of the hypotheses.


Galileo described actual experiments, although just how many of these Galileo actually performed is a matter of some dispute.

Chalmers again tries to promote his thesis that hypotheses are the basic part of science. See comments to p.12 and 13.

Galileo manufactured and sold many ingenious devices and described many experiments and results in detail. In the writing that translated to English got the title Dialogues concerning Two New Sciences (1638) his discussions virtually always proceed from observations.

He also structured experimental results using mathematical relations.


Kepler analyzed Tycho Brahe's recordings of planetary positions and developed Galileo’s theories.

Observations were also here followed by hypotheses.


Neither the inductivists nor the falsificationists give an account of science that is compatible with it.

See comment to p.93.

It is clear that the heliocentric planet system was developed through observations (of planets and orbits) that led to hypotheses (about heliocentric system) with in turn led to further confirming observations (telescopic observations and conformity with mathematically described orbits). This methodology was by Aristotle termed the inductive-deductive method, see comments to p.11 and 54.
Contrasting this, only falsification does not give an account of this development..


Inadequacies of the falsificationist demarcation criterion and Popper's response



Scientific theories should be falsifiable, that is, they should have consequences that can be tested by observation or experiment.

Now “falsifiable” is used as identical with “verifiable and falsifiable”.


One response that the falsificationist can give to this observation /that obviously erroneous hypotheses are falsifiable/ is to note that theories must not only be falsifiable, but must also be not falsified.

But this solution cannot be adopted too readily lest it eliminate everything that the falsificationists wish to retain as scientific.

A less superficial analysis of Popper’s theses demonstrates that it breaks down due to erroneous logic.

Chalmers is again wrestling with the problem that a falsifiable, and hence scientific, hypothesis has to get altered status at the moment it becomes falsified. See comments to p.62 and 74.


So it becomes allowable, according to the sophisticated falsificationist, to modify theories in the face of apparent falsifications, and even to hang on to theories in spite of falsifications in the hope that the problem can be solved in the future.

Again it is “sophisticated” to admit that Popper’s theses are not applicable. See also comment to p.74.


Popper: If we give into criticism too easily, we shall never find out where the real power of our theories lies.

It appears that “we” (Popper?) has not yet found out the where the “real power” of his theories lies.


The thrust of falsificationism is to emphasize the critical component of science.

The critical component of science is primarily based on the skeptic attitude to reject hypotheses that have not been verified by observations.


One might well wonder what is left of falsificationism once dogmatism is allowed a key role.

It would be ironic if the highly qualified version of falsificationism became so weak as to rule out nothing, thereby clashing with the main intuition that led Popper to formulate it.

Chalmers concludes his chapters about Popper’s theses.

We may conclude that Chalmers, and maybe also Popper, should have agreed with the earlier suggestion (see comment to p.59) to jump past Poppers theses described at p.59-102.




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