Popper's Alleged Falsificationism

July 9, 2011

Some people claim that Popper rejected non-scientific knowledge. They base this on a misinterpretation of Popper’s criteria of demarcation between science and pseudo-science. They elevate his criteria of demarcation to a central principle of Popper’s approach to philosophy, and mischaracterize Popper’s epistemology as “falsificationism.” They also assert things like: since Popper’s criteria of demarcation is falsifiability, but Popper accepts non-scientific ideas, Popper contradicts himself. Below is a brief essay by Elliot Temple, refuting these common misconceptions.

The demarcation criterion says that some things, including philosophy in general, are not science. It does not say they are all bad.

"Non-science is bad" is what some positivists said. Some positivists and Marxists also spread a Popper Legend. They attribute to Popper the position that non-science is bad in general, which he never claimed. (See "The Popper Legend" section of _The Philosophy of Karl Popper_ edited by Schilpp).

Popper was a philosopher with a healthy respect for non-scientific ideas such as epistemology, the scientific method, and morality (e.g. _The World of Parmenides_, ch2, addendum 2). And he didn't just *say* he respected these things, most of his publications are about them.

There is no clash between Popper's demarcation criterion and accepting that science uses non-scientific ideas. It does and has to.

For example, as Popper pointed out, all observation is theory laden. Many of those interpretative theories are non-science. Yet scientists use them; they are allowed into science. There is no problem with that. No problem generally and no problem with Popper's demarcation criterion.

By the way, calling Popper's philosophy falsificationism is also a mistake. Popper never called it that himself; that was done by non-Popperians. Popper states he never called it that in _Realism and the Aim of Science_ (p xxxi).

Here is one of the ways the "Popper's view is falsificationism" mistake happened, which may be instructive. It's related to the Popper Legend.

Positivists sought a criterion of meaning, or other positive criterion by which to specify which ideas are acceptable. When Popper spoke of the importance of falsification and empirical falsifiability, they considered using empirical falsifiability as a negative criterion: empirically unfalsifiable theories would be rejected (perhaps even as being meaningless). Thus they elevated empirical falsifiability to a central role. But Popper never did that.

Popper never had a problem with empirically unfalsifiable theories. Popper proposed many theories of this type, such as his solution to the problem of induction, his theories about the "Who should rule?" question, or his arguments against focussing debates on definitions of terms.

They are not science but they may be good theories. Then, within science, Popper praised theories with a high degree of empirical falsifiability -- theories exposed to refutation. That's because hiding theories from criticism sabotages progress and exposing them to criticism helps us know things better.

Popper also liked theories outside of science which were more open to non-empirical falsification. This can be achieved with, for example, clarity and boldness.

If a theory is not empirically falsifiable then it is not science, is what Popper said. But he didn't promote empirical falsifiability to a central tenet. And he certainly never tried to justify theories by their falsifiability (or corroboration, or anything else like that). But some people did try to justify theories thusly, so they took empirical falsifiability to a much more major principle than Popper did.

So it's because falsification wasn't central to Popper that he never called his epistemology by the name "Falsificationism". And because it was central to some misunderstandings of Popper, those misunderstandings are sometimes called by the name "Falsificationism" (and attributed to Popper).

(Read more of Elliot Temple's writing at Fallible Ideas )