The Two Fundamental Problems of the Theory of Knowledge (2009) was first published in German in 1979. It is a thick book comprising a collection of drafts and preliminary work from the years 1930 to 1933 for Karl Popper’s first published book Logik der Forschung (1934). The Logik der Forschung was not published in English until 1959 with the badly translated title Logic of Scientific Discovery, rather than Research which would have been less diverting from his message.
Popper seemed to have a habit of writing and then delaying publishing for decades. The delay in publication of the three volumes of the Postscript is the other notable example, written in the fifties and published in the eighties. It is unfortunate for generations of students that Kuhn, Lakatos, Feyerabend and others in the meantime interpreted Popper’s work so separated from his actual writings that at times they may as well have been talking about something else entirely. It is not criticism that is an issue but misattribution of Popper’s views before criticism. It reminds me of the time my Scottish grandfather was at a funeral and could not conjoin the content of the eulogy with the deceased subject, he leaned over and whispered “I think we are at the wrong funeral”.
I recommend the purchase of The Two Fundamental Problems even if one only wants to read the introduction written by Popper in 1978. The introduction is as good a synopsis some of his core themes as I have read, startling in clarity and brilliance.
Some aphoristic points:
1. Plato’s Apology of Socrates is perhaps the most beautiful philosophical work known. Socrates is a little wiser than others perhaps because he knows that he does not know.
2. For Kant, Newton’s theory is not empirically gleaned from phenomena through the senses but is derived from our understanding. Kant believes Newton’s theory is true, Popper adds that it is not necessarily so.
3. Up until the Einsteinian revolution, Newton’s theory was corroborated better than anyone could have dreamed of. For Kant Newton’s theory is justifiable science, and therefore certain knowledge. For Einstein knowledge about reality is uncertain.
4. Fallibilism destroys scientism.
5. Science is the searching for truth: not the possession of truth, but the quest for truth. The idea of truth as manifest is unfortunately widespread.
6. In Popper’s view there is only one theory of truth that is to be seriously entertained: the correspondence theory; namely the thesis that the truth of a statement consists in its correspondence with the facts. The statement, “A cat is sleeping here”, is true if and only if a cat is sleeping here, no matter what language “A cat is sleeping here” (the object language) is spoken in.
7. We must sharply distinguish between the question of whether a statement is decidable (whether we believe we can prove it true or false) and the question of its truth.
8. Universal theories are fundamentally hypothetical or conjectural because they are not decidably true. This does not mean however that they may not be true.
9. The criterion for demarcation (falsifiability) is non-empirical. It was not obtained by observing what scientists do or do not do whether by studying living scientists or by studying the history of science.
10. Theories such as the Einsteinian and Newtonian theories of gravitation have an infinite number of potential falsifiers.
11. I have strongly emphasised in The Logic of Scientific Discovery that there is almost certainly no such thing as indubitable (or final) falsification by observation.
12. The critical attitude is characterised by the fact that we try not to verify our theories but rather to falsify them. Naturally one should not dwell on errors that are easily repaired but, if possible, correct them before embarking on serious criticism.
13. It is not even possible to formulate a principle of induction that is moderately plausible.
14. The fundamental weakness of inductivism lies in its extremely popular but fundamentally erroneous tabula rasa theory of the human mind. We are active, creative, inventive, even if our inventions are controlled by natural selection. The stimulus-response scheme is replaced by the mutation-selection scheme (mutation= new action). Knowledge is not a passive expression of the “data” provided by the senses.
and last but not least
Problem of induction (Hume’s problem) : “Can we know more than we know?”
Problem of demarcation (Kant’s problem) : “When is a science not science?”
I think Popper’s answer to these problems is: we don’t know but we do guess and we can structure our guesses as criticisable and falsifiable.