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Back to Unedited Philosophy Quotes and Ramblings about Intequinism.

Author: Popper, Karl R. (Karl Raimund), 1902-1994

Book name: The Two Fundamental Problems of the Theory of Knowledge

First published 2009 by Routledge

First published in Routledge  Classics 2012

Simultaneously published in the USA and Canada by Routledge of New York, NY.

Editor: Troels Eggers Hansen

Translated from German by: John Kinory and Andreas Pickel.

ISBN: 978-0-415-61022-3 (pbk)


Reader: MD Pienaar


12 April 2012


Book 1   The Problem of Induction   Experience and Hypothesis


Page 99


' The sceptic, who first doubted the absolute truth of our knowledge, is in turn compelled to explain this (absolute) concept of truth as anthropomorphic. But what he still doubts can now no longer be expressed; for it is evident that even the concept of doubt presupposes the concept of truth. '




In the book Popper says that there is no first principle of induction and therefore logically, induction cannot prove something true. An endless regression exists at inductions. Above however he implies that truth is the first principle of inductions. Most things we say, prove, doubt, disprove have as first principle, I think today, truth. Without truth as an idea communication, science and deceit would not have existed, or is it the other way round. Was the intention of the first word ever spoken truthful or deceitful?


Page 101


' The “absolute” can be grasped only subjectively (that is, “believed”); all objective (that is, universally valid, intersubjectively testable scientific) knowledge is “relative”. “It seems to me that this pair of opposites, subjective-absolute and objective-relative, contains one of the most fundamental epistemological insights that can be gleaned from science,” writes Weyl, (15) admittedly without reference to Kant's doctrine; and he continues: “Whoever desires the absolute must take the subjectivity and egocentricity as part of the bargain; whoever feels drawn toward the objective faces the problem of relativity.”(16) '


' (15) Hermann Weyl, Philosophie der Marhematik und Naturwissenschaft (1927), p.83 [English translation by Olaf Helmer: Philosophy of Mathematics and Natural Science, rev. and augm. English ed. (1949), p. 116. Emphasis as in the German original. Tr.] '

' (16) As Weyl himself emphasises, this idea is also found in Max Born. Die Relativitȁtstheorie Einsteins und ihre physikalischen Grundlagen (1920), Introduction; and even earlier, Reininger offered a very similar statement; cf. Robert Reininger, Das Psycho-physiche Problem (1916), pp. 290 f. '


Page 107


' The rather high hopes that Kant derived from the correct insight that a general scepticism is self-contradictory have proved to be unjustified. '




When I read the above I did not agree with Popper. I thought that a general negation is self contradictory because to say something is always uncertain is a certainty of always uncertain. It is thus in effect a positive statement but a contradictory positive statement because of the always and the negation. It relates to my argument with the Burger when they changed my comment with a heading to ' Los die veralgemenings ' which I explained is a generalisation and thus contradictory.


Today I read in the Pretoria news that children should be brought up stricter than current practice. If a child is disciplined with reference to a negation is has to according to my current thoughts always be in the context of the time the disciplinary action took place. A child cannot be told to never do something or in other words always not do something. A child could perhaps be influenced to always do something if positive generalisations should be allowed. Apparently the Ten Commandments appeared in Egyptian graves in the positive as history of what was done during lifetimes of people.


19 April 2012


Page 304


' According to deductivist (sic OO) empiricism too, the thesis that natural laws can never be [demonstrably] true is equivalent to the thesis that we have no possible empirical (and certainly no a priori) justification for asserting the existence of universal states of affairs.


(We can, therefore, only assert the existence of those states of affairs that can be represented by singular statements; that is, only the existence of singular states of affairs.)


On the question whether or not experiential, empirical universal states of affairs exist, deductivism (sic OO) is in agreement with logical positivism: both answer this question in the negative. (2) '


' (2) As long as the emphasis is on the words “experiential” and “empirical”, this statement is correct. It follows that the proposition “universal states of affairs exist” is metaphysical; but it does not follow that natural laws are fiction. '




“Universal states of affairs exist” thus means that metaphysical events exist and can be investigated because it is not fiction.


21 April 2012


Page 313-314


' The more highly developed natural sciences, in particular, consist almost entirely of natural laws (universal statements): “We ought not to forget that any description of the world by means of mechanics will always be of the completely general kind. For example, it will never mention particular point masses: it will only talk about any point masses whatsoever.”(15)


Mechanics, as correctly characterised here by Wittgenstein, is a natural science according to the viewpoint of natural science. It can, however, never be included in Wittgenstein's concept of a natural science. The philosophical critique of language maintains that the putative strictly universal empirical statements of mechanics are actually pseudo-statements, and it excludes them from the domain of scientific statements, that is, it sharply demarcates “natural science” so as to keep them out. '


' (15)Ludwig Wittgenstein ', Tractatus Logico-Philosophicus (1918/1922), Proposition 6.3432.




It seems Popper categorise science according to the definition of truth by Plato in The Republic. Basic truths that Wittgenstein state. Then mechanics which includes universal statements and could thus be almost defined as metaphysical and then metaphysics which uses pseudo-statements.


Page 314


' The analysis of the pseudo-statement positions leads our discussion of the problem of induction to the problem of demarcation. This problem does not merely constitute the background of the logical-positivist concept of meaning: on closer examination it becomes evident that it is in fact the problem of demarcation that underlies the problem of induction. '


Page 316


' If we ask about the analogous demarcation criterion for statements – this is of much greater interest to us here – and avoid the subjectivist-psychologistic mode of expression, then inductivism must arrive at the following criterion,  which I call the fundamental thesis of inductivism.


All legitimate statements of science must be reducible to elementary empirical statements. In other words: the truth of all legitimate statements must depend on the truth values of some elementary empirical statements.


(“Elementary empirical statements” are to be understood as (objective) descriptions of the simplest states of affairs, which can be tested directly (in principle, by any subject) through “perceptions”; cf. Section 11.)


As long as induction, or the inference of universal statements from singular experiences, is accepted as justified, the “fundamental thesis of inductivism” proves to be an exceedingly useful demarcation criterion with the help of which natural laws can also be demonstrated to be “legitimate”. But should genuine inductive inference be regarded as impermissible and self-contradictory (Hume), then natural laws can no longer be reduced to elementary empirical statements. Put another way:


Legitimate statements can no longer be elevated to the rank of generalisation, that is, to the level of natural laws. They are cut off from natural laws by the demarcation criterion (by this very “fundamental thesis”); the boundary runs below the level of natural laws. Legitimate statements remain confined to experience, that is, to the singular. '




Be vary careful to quote Popper unless you really understand what he means. He writes in ifs a lot. If this is the case that is the conclusion. It is thus possible to quote a conclusion without quoting the premises that leads to the conclusion. '


Page 330


' We already know that only singular empirical statements can, in principle, be verified and falsified, whereas strictly universal empirical statements are, in principle, only falsifiable.


These properties can be used in order to distinguish, with sufficient precision, between singular and strictly universal empirical statements. To this end, however, it is above all necessary to define more precisely the expressions “in principle verifiable” and “in principle falsifiable”. For without such a definition, the statement “Singular empirical statements are, in principle, verifiable and falsifiable” would be ambiguous. Its wording could be so understood as to make it permissible for one and the same statement to be both true and false. Similarly, the statement “Universal empirical statements are in principle only falsifiable” could be misinterpreted as stating that universal empirical statements can, in principle, only be false.


I propose, therefore, the following more precise definition: the phrase “in principle verifiable” is to be understood as saying that no logical reasons stand in the way of empirical verification.


The statement “Singular empirical statements are, in principle, verifiable and falsifiable” is to be understood as saying that no logical reasons stand in the way of empirical verification or falsification of singular empirical statements. Similarly, “Universal empirical statements are, in principle, only falsifiable” is to say that experience can, for logical reasons, decide only their falsity but never their truth.


No logical statement justifies our saying a priori that universal empirical statements are false (otherwise they themselves would be logical contradictions, and experience could in no way decide them); we can, however, say a priori that their truth cannot be demonstrated by experience. '


Page 334


' In section 15, the statements that are a priori true and, as hypotheses, have primary probability 1, were called “empirically empty”. These (analytic) judgements state nothing about reality; experience cannot decide them. This also is why they should not be called “empirical statements” (but perhaps “conceptual analyses”) '




My truth to creativity explanation of the paper on the table has a probability of 1 and can be demonstrated.


22 April 2012


Page 351-353


' From a historical perspective, the systematic attempt by positivism to discredit Kant's project has, undoubtedly, seriously harmed the development of epistemology (and of the “scientific world view”).

(See, for example, the historical address (4) to the Prague Congress [1929] on the “epistemology of the exact sciences”. One searches in vain for Kant's name among those of the very many philosophers of all periods. Finally we find it, when Franz Brentano is boldly praised (5) for having “spared himself the Kantian interlude”. We can only wonder: Why Brentano in particular? Does such an evaluation of Kant not suggest that it should, instead, have been this or that positivist boasting of this?)


In order to emphasise my commitment to Kant, if not to Kant's apriorism. I should like to quote in full several paragraphs from the Critique of Pure Reason (“The Regulative Employment of the Ideas of Pure Reason”).(6) This passage might well serve as motto for my work. In any event, it is appropriate to quote it at this point in the argument, which deals with dialectical corroboration and therefore with historical justification, for it sheds light on one of Kant's ideas:


“If however, the universal is admitted as problematic only . . . the particular is certain but the universality of the rule of which it is a consequence is still a problem. Several particular instances, which are one and all certain, are scrutinised in view of the rule, to see whether they follow from it. If it then appears that all particular instances that can be cited follow from the rule, we argue to its universality, and from this again to all particular instances, even to those which are not themselves given. This I shall entitle the hypothetical employment of reason.


“The hypothetical employment of reason . . . is not, properly speaking, constitutive, that is, it is not of such character that, judging in all strictness, we can regard it as proving the truth of the universal rule that we have adopted as hypothesis. For how are we to know all the possible consequences which, as actually following from the adopted principle, prove its universality? The hypothetical employment of reason is regulative only; its sole aim is, so far as may be possible, to bring unity into the body of our detailed knowledge, and thereby to approximate the rule to universality.


“The hypothetical employment of reason has, therefore, as its aim the systematic unity of the knowledge of understanding, and this unity is the criterion of truth of its rules. The systematic unity (as a mere idea) is, however only a projected unity, to be regarded not as given in itself, but as a problem only. This unity aids us in discovering a principle for the understanding in its manifold and special modes of employment, directing its attention to cases which are not given, and thus rendering it more coherent.”


I have not quoted this passage until now because it is, perhaps, only at this point that it can be fully appreciated. It supports my view that the thread of the epistemological debate has to be rejoined at the point where post-Kantian metaphysics had torn it: with Kant. '


' (4) OttoNeurath, Wege der wissenschaftlich Weltauffassungen” [“Ways of the Scientific World View. Tr.] Erkenntnis 1 (1930), pp. 106 ff. '

' (5) Neurath, op. cit., p. 120. '

' (6) Immanuel Kant, Kritik der reinen Vernunft (2nd ed., 1787), pp. 674 f. [English translation by N. Kemp Smith (1929), 1965, Critique of Pure Reason, pp. 534 f. Tr.]



Book II   The Problem of Demarcation   Experience and Metaphysics




24 April 2012


Page 471


' . . This, the “demarcation problem” (Kant's question about the limits of scientific knowledge), can be defined as the question about a criterion for distinguishing between “empirical scientific” and “metaphysical” assertions (statements, systems of statements). Wittgenstein's attempted solution (3) is that the “concept of meaning” provides this demarcation: every “meaningful statement” (as a “truth-function of elementary statements”) must be fully reducible, logically, to (singular) observation statements (it must be derivable from them). If a supposed statement cannot be so derived, it is “meaningless”, “metaphysical”, it is a “pseudo-statement”: metaphysics is meaningless. With this criterion of demarcation, positivism seemed to have achieved a more radical overthrow of metaphysics than had earlier anti-metaphysical positions. But along with metaphysics, this radicalism destroys natural science also: natural laws, too, are not logically derivable from observation statements (the induction problem!); under consistent application of Wittgenstein's criterion of meaning, they would become nothing but “meaningless pseudo-statements” or “metaphysics” also. '


' (3) Ludwig Wittgenstein, Tractatus Logico-Philosophicus (1918/1922) '