Popper, Karl ; Conjectures and Refutations, preface i and ii

Popper, Karl ; Conjectures and Refutations – the growth of scientific knowledge (1968, c1963)

Preface

Thesis : we can learn from our mistakes ; this book puts forth a theory of knowledge and its growth.

"...conjectures are controlled by criticism; that is, by attempted refutations, which include severely critical tests.  They may survive these tests, but they can never be positively justified: they can neither be established as certainly true nor even as “probable” (in the sense of the probability calculus).” (vii)

Me: there are many “problems” we don't have in common – and problems, like aims [see below] can change…

“As we learn from our mistakes our knowledge grows, even though we may never know – that is, know for certain.”

Me: evidently we can we know for certain that a theory is wrong, or at least incomplete, though...

According to Popper, the fact that a theory can be falsified is what makes it scientific (it has not been proved, but it has not been disproved…):

“those among our theories which turn out to be highly resistant to criticism, and which appear to us at a certain moment of time to be better approximations to truth than other known theories, may be described, together with the reports of their tests, as ‘the science’ of that time.  Since none of them can be positively justified, it is essentially their critical and progressive characters – the fact that we can argue about their claim to solve our problems better than their competitors – which constitutes the rationality of science.” (vii)

Popper also applies this "rationality of science" widely: to "the problems of the philosophy and history of the physical sciences and of the social sciences to historical and political problems" (viii)

Preface to second ed.

“all our knowledge grows only through the correcting of our mistakes” (ix)

Popper goes on to say that our aims (me: goals) can be changed by trial and error as well.

Me: But don't we sometimes, especially when we are young, simply learn new things as we are exposed to them, apart from any mistake correction? (not to preclude the possibility that children have not only an instinct for induction, but also a disposition to form certain judgments and ideas, i.e. that our minds anticipate this acquisition of knowledge)  If that is not growth in knowledge what is it?

My summary: -

My critique: Right away, we see some problems with the discussion of problems.  Surely, some situations we can agree are problems, more or less: diseases for example.  But other things, like figuring out the exact "structure of reality" (construed as impersonal a priori) is not going to be a problem that all share.  It also seems plain wrong to say that all of our knowledge grows *only* through mistake correction. 

~Nathan