A Philosophical Mistake

I had intended today to write a weblog entry on the theory of conjectural knowledge, but will save that for another time. When doing some research, I happened upon Ten Philosophical Mistakes by Mortimer J. Adler, and was drawn to Chapter 4: Knowledge and Opinion. Therein, I was surprised to discover the following paragraph:

According to Sir Karl Popper, one of the most eminent philosophers of science in our time, the line of demarcation between knowledge and mere opinion is determined by one criterion: falsifiability by empirical evidence, by observed phenomena. An opinion, a view, a theory, that cannot be thus falsified is not knowledge, but mere opinion, neither true nor false in any objective sense of those terms, Popper places the experimental and empirical sciences on one side of the line, and theoretical philosophy on the other side of the line

The utter mangling Adler performs on Popper's views would take an essay to untangle satisfactorily. The following will have to suffice. (1) the falsifiability criterion was not proposed to demarcate between 'knowledge and mere opinion', but to demarcate between science and nonscience, (2) to say that some theory is unfalsifiable does not mean that 'it is not knowledge, but mere opinion, neither true nor false', but simply that cannot be tested against any empirical observation, and (3) Popper said that all knowledge is conjectural i.e. opinion, and that there is no such thing as knowledge in the sense which Adler means here i.e. justified belief.

It is fair criticism to say that Popper was not always crystal clear when expressing his views, especially when they were still developing (leading to some inconsistent use of language) but for someone who described Popper as 'one of the most eminent philosophers of science in our time', Adler would have done well to pay closer attention to what Popper actually said, and perhaps refrained from the common error of assuming that Popper's falsificational theory of science is just logical "positivism with a twist".

Comments

[Dale Nichols]

Hmmm... I guess that if it's worth saying once, it's worth saying again.

Anyway, this looks like a blog worth looking at and I'm going to bookmark it. Keep up the good work.