This is an Accepted Manuscript of an article published by Taylor & Francis Group in International Studies in the Philosophy of Science on 06 January 2011, available online:

http://www.tandfonline.com/doi/abs/10.1080/02698595.2010.522413#.U8luVPmqmo0

Marco Buzzoni

Rethinking Popper and His Legacy

Rethinking PopperROBERT S. COHEN AND ZUZANA PARUSNIKOVÁ (Eds.)Dordrecht, Springer, 2009xii + 431 pp., ISBN 9781402093371, €145.55 (hardback)

Popper’s Legacy: Rethinking Politics, Economics and ScienceRAPHAEL SASSOWERStocksfield, Acumen, 2006vii +151 pp., ISBN 9781844650668, £40.00 (hardback); ISBN 9781844650675, £14.99 (paperback)

Karl Popper’s Philosophy of Science: Rationality without FoundationsSTEFANO GATTEILondon, Routledge, 2009xii + 137 pp., ISBN 9780415378314, £85.00 (hardback)

1. Introduction

1

Addressing the clear and at the same time difficult problem of thedistinction between historical or significant facts and non-historical or insignificant ones, Karl R. Popper noted that we should “write that history which interests us”: history must be selective unless it is to be choked “by a flood of poor and unrelated material” (Popper 1957, 139). In Benedetto Croce’s words, all true history is “contemporary history” (Croce 1938, 5).

This important methodological principle can be clarified by referring to an often neglected aspect of the significance of all cultural products, be they historical facts, texts or an author’s thoughts. The significance of a text is not something that is already contained in it, but something that grows in proportion with the interpretations that bring that text into new relations to other works, problems, points of view, interests, and values. The meaning of Plato’s philosophy for Plato and his contemporarieswas necessarily different from its meaning for us: it is impossible for us to abstract Plato’s philosophy from its subsequent interpretations (by Aristotle, Martin Heidegger, etc.) which have accordingly become constitutive of its meaning. The “genuine” Plato is not something static, a “completed being” waiting to be discovered beneath many layers of interpretation, but something changing, and yet objective and real. If Plato couldre-read himself today, he would interpret his own texts differently.

According to Popper, however, when we adopt a selective point of view we must pay great attention to avoid the circularity whichaffects historical interpretations to the extent that they contain“only such facts as fit in with preconceived theory” (Popper 1945,vol. 2, 294). Any attempt to identify “what is living and what is dead” in an author (to use Croce’s expression) always runs the risk of giving a one-sided or subjective picture of the author’s views. This risk can be avoided only if the adopted point of view is used so as not to exclude possible retroactions from the text, of which it selects and highlights some aspects rather than others. We can view a text from different perspectives, but what is seen remains as to its content independent of the perspective that was used to discover it and may support or falsify certain interpretations.

Recent years have seen the attempt to bring Popper’s thought to bear on current philosophical debates by showing how he can

2

help us find solutions to today’s problems. Three recently published books on Popper are representative, in different ways, of this hermeneutic trend. Raphael Sassower’s Popper’s Legacy: RethinkingPolitics, Economics and Science gives a particular reading of Popper’s ideals of personal freedom and responsibility through unusual comparisons with well-known theses of Karl Marx and by drawing close affinities with today’s sociology of knowledge, postmodernism, and feminist philosophy of science. Rethinking Popper (henceforth RP), edited by Robert S. Cohen and Zuzana Parusniková, pursues the same aim with respect to a larger set of topics. This book, which contains many papers read at a conference held in Prague in September 2007, is organised in four parts: I. Reason, Logic, Science; II. Epistemology, Methodology, Evolution; III. Society, Politics; IV. Ethics, Economics, Education. Lastly, Stefano Gattei’s Karl Popper’s Philosophy of Science: Rationality without Foundations is a general introduction that stresses Popper’s approachas an original alternative to the foundationalism prevalent in Western philosophy.

Various problems raised by these books deserve detailed consideration. However, given our limited space, we can only sketch two main issues: first, Popper’s social notion of rationality and objectivity and its similarities with Marx, with the sociology of science, with feminist epistemology and with postmodernism, and, second, Popper’s antifoundationalism.

2. Popper, Marx, and the Sociology of Knowledge

Sassower’s book deserves credit for some novel and interesting aspects. Its more general point is certainly sound: Popper’s legacy must be considered “as a whole, trying not to isolate this or that statement, this or that idea from the rest of his work” (Sassower, 3). Sassower highlights the moral dimension of Popper’swork and relates his political and economic ideas to his methodology of science (Sassower, 7 and 125).

Many interpreters (e.g. Shearmur 1996; Fuller 2004), includingsome of the contributors to RP, would agree with such highly plausible statements. More doubtful, even though it represents themost distinctive contribution of Sassower’s interpretation, is thethesis that Popper’s views have many important affinities not only

3

with postmodernism, but also with Marx’s thought and with feministphilosophy of science. According to Sassower,

if Marx’s views are read as (a) an attempt to study the forces of political economy historically, (b) an attempt tocritically revise Hegel’s idealism and put it on its head, so to speak, (c) an attempt to add empirical lustre to philosophical speculations, (d) an attempt to deconstruct classical economic thought with a keen eye on the methods it used, and (e) a theory open to future critical assessment because of its predictions, then Marx comes closer to Popper’s own ideals. (Sassower, 27)

It is certainly true that there are more points in common between Popper and Marx than there would seem to be at first sight. Nevertheless, these points tend to be general in nature, and Sassower moreover invariably stresses the similarities more vigorously than the relevant differences. Furthermore, some of these affinities could be better understood with reference to other authors. For example, a common recognition of the importanceof the social character of science (e.g. Sassower, 90–91) is too vague to support the conclusion that Popper was influenced by Marxrather than—in my view more plausibly—by the tradition of German social democracy, perhaps through Bertrand Russell’s book on this subject. It is true that Eduard Bernstein’s influence on Popper has been persistently ignored and is still an interesting subject for future investigations. However, it is very natural to attribute various of the affinities with Marxian thought highlighted by Sassower to the influence exercised on Popper by Bernstein’s revisionism. First, Bernstein’s impact on Popper is borne out by the fact that the objections to Marx in The Open Society are the same as those raised by Bernstein (1899). Second, in the same work (where incidentally the mistaken initial, “A. Bernstein”, has not yet been corrected) Popper says that Bernstein’s “revisionism”, “in fact, gives up Marxism altogether; it is nothing but the advocacy of a strictly democratic and non-violent workers’ movement” (Popper 1945, vol. 2, 384). Finally, Popper names Bernstein’s “chief works” among the books that his father possessed (Popper 1974a, 6).

4

The comparison with feminist epistemology and philosophy of science raises similar problems. Sassower stresses the similarities between Popper’s “situational logic” and Donna Haraway’s “situated knowledge” (Sassower, 96ff.). Even though he is right in holding that Popper deserves credit “for formulating ideas and methods of inquiry that are picked up in other contexts without acknowledging their intellectual antecedents” (Sassower, 96), here too there are other authors with whom more suitable comparisons would be possible. For example, Haraway’s situated knowledge is better seen as influenced by Hilary Putnam’s critiqueof the “God’s Eye point of view” (Putnam 1981, 49). A more fittingcomparison would have been with Helen Longino’s claim that objectivity is not attainable by an isolated individual, because it requires the essentially social or intersubjective context of scientific research (compare Popper 1945, vol. 2, 294, with Longino 1990, 12).

Sassower’s comparison of Popper with postmodernism also goes too far:

to be postmodern in relation to anything scientific, for example, is to be a critical rationalist in the tradition of Popper, Agassi and Jarvie. That is, to be critical of the scientific establishment is a social, political, economic and moral posture that lowers the threshold for debate and dismisses the gatekeepers, and always recognizesthat the best we can accomplish is to deal with multiple truths (small “t” and plural). (Sassower, 127)

Sassower claims that he does not wish “to turn Popper into a postmodernist nor the postmodernists into Popperians” (Sassower, 134). This statement would require some acknowledgement of the fact that the differences between Popper and the postmodernists are deeper than their similarities. In this regard, one could mention Popper’s rejection of relativism and irrationalism, his critique of the myth of the framework, his idea of objective truthas correspondence to the facts, his notion of science as a search for absolute truth, and his quasi-Platonic theory of World 3.

Sassower says he will ignore Popper’s theory of World 3 (Sassower, 7). It is hard to see how it is possible to ignore a theory that Popper held for the last thirty years of his life and

5

which in his eyes played a very important role in the rejection ofinstrumentalism and relativism. Certainly, from Sassower’s sociological viewpoint there is hardly a place for such a theory. However, in ignoring it he simply draws attention to the limitations of his interpretation. Sassower’s point of view works for some questions but not for others: it works for comparing Popper and Marx but not for appraising the theory of World 3, which is also an explicit rejection of Marx’s theory of the economic and social causation of human thought. Moreover, if the theory of World 3 had no social and political implications, it would not be plausible to maintain—as Sassower does—that ethical and political concerns run deep through Popper’s philosophy.

One may object that World 3 is essentially a social and institutional reality. Other contributors to RP, as a matter of fact, stress Popper’s affinity with postmodernism by bringing his views close to the sociology of scientific knowledge. (For the claim that Popper’s conception of rationality is intrinsically social, see Ian Jarvie, ‘Popper’s Continuing Relevance’, RP, 229; John Wettersten, ‘Popper and Sen on Rationality and Economics: Two(Independent) Wrong Turns Can Be Remedied with the Same Program’, RP, 369–378; Jeff Kochan, ‘Popper’s Communitarianism’, RP, 287–303;Jarvie and Wettersten are well-known for their emphasis on the social aspect of Popper’s philosophy: see Jarvie 2001 and Wettersten 2006). In David Bloor’s phrase “local situation”, Sassower sees an important affinity with Popper’s “situational logic” (Sassower, 102–104). Kochan goes much further: Popper is “amethodological individualist in name only” because his focus on institutions and situations makes him a “communitarian”; Bloor wasmistaken in taking Popper “to be a foe when he was, in fact, a friend” (Kochan, RP, 295 and 297).

In my opinion, it is right to say that World 3 is, strictly speaking, a social institution. However, if one stresses similarities at the expense of fundamental differences one will inevitably end up with a false picture of reality. In the first place, one has only to call to mind Bloor’s strong programme to note how deep the differences are. The assumption underlying the four principles of his programme (causality, impartiality with respect to truth and falsity, symmetry, reflexivity; Bloor 1991, 7) is a radical naturalism which denies in principle the followingdifferences: between philosophy and science (principle 4); between

6

the grounds on which people act and the causes that relate natural events to one another (Bloor 1991, 36–37); and between the human and the natural sciences (Bloor 1991, 23: empirical findings and theoretical models in the human sciences work “in exactly the sameway as they do in any other science”).

Now, Popper upheld all three differences: the first against neopositivism ( “my theory is not empirical, but methodological orphilosophical, and it need not therefore be falsifiable”, Popper 1974b, 1010); the second against the reduction of humans to machines and against the causal theory of naming (Popper 1963, chap. 12); the third against the naturalistic leanings of historicism, based on the fact that situational analysis is the fundamental difference between the social and the natural sciences(Popper 1957, §29).

Second, and more importantly, the fundamental distinction madeby Popper’s Logik der Forschung between the psychology and the logic ofscientific knowledge (Erkenntnispsychologie vs. Erkenntnislogik), further developed in the theory of World 3, undermines Bloor’s strong programme. Bloor’s strong programme, it will be remembered, was intended to eliminate the exceptions made by Karl Mannheim and to extend the social causation of thought not only to mathematics andnatural science, but also to the sociology of knowledge itself.

The distinction between the psychological and the logical analysis of scientific knowledge is Popper’s formulation of Immanuel Kant’s opposition of quid facti and quid juris (Popper 1968, 31), according to which validity cannot be derived from experience, no matter what this experience (psychological, social,economic, etc.) may be. No plausible interpretation of Popper’s thought can ignore this distinction, which marks the irreconcilable difference between Popper and the sociology of scientific knowledge. Despite all the important divergences between the two thinkers, on this point Popper sides with Kant. The validity of our claims cannot be reduced to real (psychological, social or historical) causal factors. In my opinion, Popper is quite right in this. Any attempt to reduce reason to empirical causal factors contradicts itself, since it presupposes it own validity as a normative instance that it is irreducible to those factors.

This is, in Popper’s view, one of the fundamental teachings ofWorld 3 theory. This theory showed that the psychological,

7

historical, and sociological investigation of the origins and development of human culture is secondary with respect to the analysis of culture’s objective, or structural, content, be this analysis scientific, sociological or political. Consequently, the affinity between Bloor’s local situation and Popper’s situational analysis vanishes as soon as we view the meaning of the latter in the light of World 3. The situational analysis takes advantage of the results of the logical analysis of knowledge, by applying themto the psychological or social context of discovery:

the problems of the second category [i.e., those concerned with the produced structures themselves] are basic for understanding the production problems: contrary to first impressions, we can learn more about production behaviour by studying the products themselves than we can learn aboutthe products by studying production behaviour. This [...] thesis may be described as an anti-behaviouristic and antipsychologistic thesis. (Popper 1972, 114)

If one bears in mind that, with regards to science, the “products”of World 3 are above all scientific theories, one sees the affinity of this passage with Imre Lakatos’s concept of the rational reconstruction of the history of science (rightly criticised by Thomas S. Kuhn and Bloor). Philosophy of science, asthe logic of scientific research, has an important priority over history of science and the description of the actual genesis of scientific theories. I do not deny that in Popper there are some ‘sociological’ elements which, developed to their ultimate logicalconsequences, lead to Kuhn and to Bloor’s sociology (I have myselfmaintained this view, and cannot dwell upon it now: see Buzzoni 1982, 149–154). I am arguing only that there are other, far more important elements in Popper that make him the irreducible enemy of any sociology of science of the type inaugurated by Kuhn and Bloor.

3. Popper between Antifoundationalism and Platonism

As we have just seen, the view that Popper manifests a postmodernist tendency because of his great affinity with the

8

sociology of knowledge is untenable. It is much more plausible to claim that he bears a strong postmodernist trait because of his antifoundationalism (see above all Parusniková, “Ratio Negativa—The Popperian Challenge”, in RP, 44; cf. also Parusniková’s review of Miller 2006, RP, 419).

The view that Popper’s greatest originality lies in his antifoundationalist concept of rational criticism is very widely held among his followers, who uphold it above all on the grounds that he is taken to have found a “middle way” equally distant fromdogmatism and relativism (for example Joseph Agassi in RP, 358). Gattei’s book adheres to this interpretation of Popper, whose philosophy is said to offer “an account of how scientific knowledge can be objective and rational without being certain” (Gattei, 1).i

One must admit that Popper tried to avoid both dogmatism and scepticism. However, he did not succeed in solving this dilemma and his philosophy manifests different and even opposing tendencies. In particular, his antifoundationalism contradicts other key elements of his philosophy.

As I said above, Popper’s chief difference with the sociology of knowledge consists in the qualitative distinction that he makesbetween the logical and the psychological analyses of knowledge. Iremarked that the introduction of “situational analysis” in the theory of World 3 developed this distinction in a doubtful, but certainly not antifoundationalist direction. Now I will try to be more precise, by showing that Popper’s theory of World 3 and his theories of objective truth and verisimilitude affect the distinction between the logic and the psychology of scientific knowledge in a way which—even though it is at best doubtful—is quasi-Platonic and hence surely not antifoundationalist. In this sense, the theories of absolute truth, verisimilitude, and World 3pose the most serious obstacles to re-readings of Popper as a postmodernist based on his alleged radical and/or coherent antifoundationalism.

As is well known, for Popper truth is objective or absolute inthe sense that it is correspondence to facts and, as such, “above human authority”. However, this concept of truth does not give us a criterion of truth, a means of finding it, or of being sure thatwe have found it (e.g. Popper 1963, 27, 223–228, 407; Popper and Kreuzer 1982, 108–109).

9

Popper is ambivalent on this point. On the one hand, using a clearly antifoundationalist move derived from the sceptical tradition, he severs truth from the criteria of truth and hence from certainty; on the other hand, he tacitly unites them again when he says that the falsification of some of our conjectures presupposes the existence of an absolute truth or an absolute correspondence to the facts. This hypostatized and unattainable ideal, which “corresponds to all facts, as it were, and, of course, only to real facts” (Popper 1963, 234), is the object of an immediately given (and as such unquestionable) intuition that plainly contradicts Popper’s fallibilism:

The status of Truth in the objective sense, as correspondence to the facts, and its role as a regulative principle, may be compared to that of a mountain peak usually wrapped in clouds. A climber may not merely have difficulties in getting there – he may not know when he gets there, because he may be unable to distinguish, in theclouds, between the main summit and a subsidiary peak. Yet this does not affect the objective existence of the summit;and if the climber tells us ‘I doubt whether I reached the actual summit’, then he does, by implication, recognize theobjective existence of the summit. (Popper 1963, 226)

Is it really necessary to accept the objective existence of the mountain’s summit, i.e. of an absolute truth? Certainly not if onekeeps in mind the separation between truth and the criteria of truth. A climber who wishes to reach the summit of the mountain must have previous experience of other mountains: this is what lends plausibility (of an inductive kind, but I do not wish to raise this problem now!) to the climber’s belief that the present mountain too has a summit. Otherwise there would be no contradiction in assuming that there is no summit and that the climbing will never end.

Popper’s example of a missile guided by a computer makes this point clearer:

10

The missile is guided by feedback, that is to say, by the relative evaluation of tentative predictions, precisely of the kind demanded by the theory of verisimilitude. If the computer can transform the parameters into an equivalent set for which the evaluations of the predictions are reversed, how can it ever succeed in its task? And if it does succeed, by the method of comparing and evaluating a sequence of false predictions, why cannot we do the same? (Popper 1976, 158)

The answer to the last question is very easy. The missile, unlike us, is given accurate information about its target; unlike the missile, we are unable to recognize our target even when we have found it. Here Popper runs into a dilemma. On the one hand, his acceptance of criteria of progress towards the truth would seem tocommit him to the notion of a necessary progress towards the totality of true propositions: in this view, we would slowly approximate to the absolute truth just as Popper’s missile does toits target. On the other hand, his insistence—more consonant with the main trend of his thought—that we have no criterion for recognizing the approximation to the truth is a decisive step in the direction of a certain kind of scepticism about scientific progress.

This tension between different tendencies also underlies the theory of World 3, developed during the later period of Popper’s thought. Popper notes that, even though World 3 has much in commonwith Plato’s world of ideas, it is very different as to some fundamental aspects: first, Plato’s world of ideas is inhabited byconcepts, essences, the natures of things, rather than by theories, arguments or problems; second, Plato’s world of ideas isdivine, unchanging and timeless, while Popper’s World 3 is human-made and changing; third, Plato’s world of ideas contains only truths, while Popper’s World 3 contains not only true theories butalso false and invalid ones, and especially arguments, open problems, conjectures, and refutations (Popper 1972, 122–123 and 156; Popper 1974b, 1051 and 1066; Popper and Eccles 1977, 43).

I will confine my attention to the third difference, which is the most important for the present discussion. On the one hand, the claim that World 3 contains, as well as true theories, also

11

false and invalid ones together with arguments, open problems, conjectures, refutations, etc. marks both the culmination of Popper’s antifoundationalism and a radical novelty in traditional metaphysics. Moreover, it is perfectly consistent with Popper’s fallibilism, which regards all theories without exception as conjectural, i.e. as destined to be falsified sooner or later. However, Popper does not seems to be fully aware of the consequences of this trait of World 3. As Gregory Currie rightly noted, Popper’s World 3 is pluralistic in a sense in which traditional Platonic metaphysics is not, and which deprives World 3 of any normative role (Currie 1978, 426–427). World 3 cannot help us establish the truth or falsity of any theory because it contains both true and false theories, valid and invalid standards.

On the other hand, this line of Popper’s thought, which reappears in World 3 with the radical separation of truth from itscriteria, that is from certainty, is seriously at odds with another, equally important line of thought, which virtually identifies truth with certainty. Popper offered a revised form of J. B. S. Haldane’s refutation of materialism. Haldane claimed that, if materialism were true, we could not know that it is true because the laws of chemistry, not of logic, would determine our materialist opinions. According to Popper, Haldane’s argument cannot be upheld in this form. A computer works on physical principles, but also according to the laws of logic. In order to improve the argument, Popper noted that a computer can make mistakes and these can be detected only by referring to “the logical standards of truth and validity”. These are “abstract, non-corporeal Word 3 standards” (for example, “an inference is valid if and only if no counter-example to this inference exists”), which make it possible to distinguish between valid and invalid inferences (Popper and Eccles 1977, 75–78).

This argument is incompatible with the “pluralist” view according to which World 3 contains both valid and invalid rules of inference and hence cannot provide univocal rules for recognizing invalid inferences. Here, on the contrary, World 3 provides criteria of truth or validity; consequently there is no radical separation between logical validity and certainty, and World 3 becomes closer to Plato’s world of ideas. Moreover, in both cases we have to do with standards that are external to the

12

knowing subject and hence cannot be reconstructed in the first person (every reconstruction would involve the possibility of error, to be eliminated by reference to a further standard of World 3, and so on). Accordingly, only a sort of Platonic νóησις could grasp these standards.

Now, these considerations call in question Gattei’s view that the main inspiration of Popper’s thought—even though only from theLogik onward—is antifoundationalism. How does Gattei deal with the difficulties raised by Popper’s theories of absolute truth, verisimilitude, and World 3? Since his book is a general introduction to Popper, he cannot avoid these topics and he at least hints at the new notions introduced by Popper (Gattei, 42–43and 54). However, Gattei fails to explain how Popper’s new theories of absolute truth, verisimilitude, and World 3 are compatible with his own overall re-reading of Popper as a coherentantifoundationalist.

Jarvie attempts to solve this difficulty in a different way. He claims that Popper was a coherent antifoundationalist only in certain limited periods of his thought. In his contribution to RP, Jarvie rejects the practice of treating Popper’s philosophy as a whole and advocates a division into three periods. Popper “had a long and fecund philosophical career working out the consequences of his central non-justificationist view”; accordingly “there would be changes and shifts in his ideas over that long span” (Jarvie, “Popper’s Continuing Relevance”, RP, 218).

Discontinuities in the development of Popper’s thought have been noted at least since his formulation of World 3 theory. Henryk Skolimowski (1974) was to my knowledge the first to make a clear-cut distinction between two periods, before and after 1960: one “methodological”, the other “metaphysical”.ii Other critics have proposed other distinctions. None of these periodizations is mentioned (let alone discussed) by Jarvie.

Jarvie attempts to confine Popper’s antifoundationalism to the“critical” phases of his thought, thereby excluding the theory of World 3. The later Popper, he says, is after all only “a residual category, leaving open the question of the internal consistency between works from the different periods” (Jarvie, RP, 219).

This view, however, does not answer the objections I raised against Sassower and Gattei. First, it is hardly plausible to claim that the later phase of Popper’s thought, including the

13

theory of World 3, is merely a “residual category”, since it comprises fallibilism and antifoundationalism, positions which Popper held up to his death.

Second, as we have noted, the thesis of the irreducibility of the logic of knowledge to the psychology of knowledge is not limited to one phase of Popper’s thought, but is present, in different ways, throughout it. This poses a serious problem not only for those who interpret Popper as being very close to the sociology of knowledge or to postmodernism, but also for those whointerpret him as a radical and/or coherent antifoundationalist.

It is important to note that these considerations do not wholly block the attempt to interpret Popper as an antifoundationalist, because Popper himself oscillates between antifoundationalism and the need to counteract subjectivism and relativism by providing for a relative validity of knowledge and arelative ethical foundation of action.

Before concluding, we will briefly discuss the debate on the justification of critical rationalism, which displays the same oscillation. The works we are concerned with here could not avoid this, which is a key problem for any antifoundationalist position if it is to steer clear of pure scepticism. For Popper the adoption of the critical attitude, needed to recognize the validity of an argument or an experience within a critical discussion, is an “irrational faith in reason” or “a moral decision” (Popper 1945, vol. 2, chapter 24, §§2–4). However, William W. Bartley holds that this is “an excuse for irrational commitment”, leading to the primacy of irrationalism (Bartley 1984, 103). For him, “Comprehensive Critical Rationalism” (CCR) isthe only coherent position: all the beliefs held by a rationalist can and should be open to criticism, including rationalism itself (Bartley 1964, 30).

Bartley’s rejoinder has given rise to an interesting discussion in which many of Popper’s followers have taken part. According to John Watkins, for example, CCR leads to a “dictatorial strategy” or to a “reinforced dogmatism” in Popper’s sense: “in support of the claim that CCR is criticisable we are challenged to criticise it in a certain way—namely, by trying to show that it is uncriticisable!” (Watkins 1969, 60. Among the most importantcontributions to this debate are Miller 1994, 2006, and Musgrave 1999).

14

In RP there are many interesting contributions that, with different results, follow Bartley’s approach by focusing on the logical aspect of this sort of paradox (Gunnar Andersson, “Critical Rationalism and the Principle of Sufficient Reason”, 28; Darrell P. Rowbottom and Otávio Bueno, “Why Advocate Pancritical Rationalism?”, 81–89). Andersson for example says that the Münchhausen trilemma arises only if the principle of sufficient reason is assumed, explicitly or implicitly. To solve this problem, it is enough to reject that principle (Andersson, RP, 28).Other contributions, however, such as those of Parusniková

(Parusniková, “Ratio Negativa—The Popperian Challenge”, RP, 44) and Gattei (Gattei, 77), provide ethical rather than logical argumentsfor rationalism. Popper himself, in The Open Society, had started on this path. And Hans Albert, to mention only one other outstanding exponent of critical rationalism, noted that the “decision” in favour of rationalism is a “moral decision” of a “higher level, which constitutes the basis of science and ethics” (Albert 1972, 167).

However, both the logical and the ethical foundations of rationalism are beset by many difficult problems ultimately arising from the fundamental tension in Popper’s philosophy discussed above. For example, Andersson’s rejection of the principle of sufficient reason cannot be wholly arbitrary. Otherwise, this rejection would be a very irrational decision indeed. If, however, we concede that there are reasons in favour of this decision, the obvious question arises: for what reasons should we accept these reasons? If one follows Popper in regardingcritical rationalism as an attitude, one is hardly better off, because one then faces the question whether or not a rationalist attitude is preferable to an irrationalistic one. Unless one rejects the question, any answer must be based on either some sortof justification or on a decision that cannot be made by reason.

An ethical defence of rationalism raises a similar dilemma despite initially looking more promising. How are moral standards to be conceived if they are to be capable of bearing the weight ofa decision in favour of critical rationalism? On the one hand, if they are too weak, and especially if they are weaker than arguments based on logic or experience, they cannot solve the problem of the basic irrationality of the decision in favour of rationalism. On the other hand, if moral standards are stronger

15

than arguments based on logic or experience, an appeal to morality—as noted by Friedrich Nietzsche and repeatedly stressed by antifoundationalist thinkers—is an appeal to a foundation and hence incompatible with a coherent antifoundationalism.

I will not take sides in this dispute. I will limit myself to saying that I am convinced that the solution of this problem requires a transcendental point of view that precedes the distinction between knowledge and moral action. A perspective of this kind on this problem—even though not one with which I fully agree—was used by Karl Otto Apel, first during a debate with Hans Albert which lasted for many years in the German-speaking world (for example Apel 1975, 1988; Albert 1975, 1982), and later in a debate with Jürgen Habermas, in which also methodical constructivists from the Erlangen school took part (e.g. Habermas 1983, 87–96, 105ff.; Habermas 1984, 174–183; Gethmann and Hegselmann 1977). For Apel, as is well known, to raise the question about the reasons for a rational attitude presupposes validity claims concerning intelligibility, truth, rightness, and truthfulness, which are the conditions of possibility of all argumentative discourse.

Neither of the two books and none of the contributions to RP pays any attention to these debates. This is regrettable both because these debates relate directly to a fundamental aspect of Popper’s antifoundationalism and because they raise a question which is at the heart of all the works we have been discussing—namely whether there is an ethical root of rationality.

4. Conclusions

Hans-Georg Gadamer wrote that in order to highlight an aspect of atext that we regard as important we must push into the background,or even neglect completely, all other aspects. This is what he means by “interpretation” (Auslegung; Gadamer 1986, 389).

However, as we noted at the beginning, while it is true that all texts must be interpreted from a particular point of view which, referring to certain cognitive interests or values, selectsand illuminates only partial aspects of that text, it is necessaryto use this point of view in a way that does not exclude possible

16

retroactions from the object.The works we have reviewed are good examples both of the

fruitfulness and of the limitations of this problematic aspect of interpretation. On the one hand, their authors re-read and interpret Popper from points of view that are relevant to important contemporary debates in philosophy, both in the field ofethics and politics and in the field of epistemology and systematic philosophy: they illuminate aspects of Popper’s heritage which had so far been neglected in whole or in part. On the other hand, it is hard to see how overall re-interpretations of Popper’s philosophy in terms of the sociology of science, postmodernism or antifoundationalism can accommodate the importantdistinction between logic and psychology, developed by Popper in the theories of absolute truth and of World 3.

Popper’s philosophy grew out of the attempt to harmonize different tendencies which, interacting with one another, producedthe many oscillations and inconsistencies that affect the different phases of the development of his thought. Thinkers influenced by Popper tend to deal with the inherent complexity of his thought by privileging the aspects and tendencies they find most congenial. Simplifications and unilateral reconstructions have often resulted. The most serious challenge to this way of rethinking Popper comes from Popper himself, who never attempted to simplify problems for the sake of finding easy solutions. Amongthe most fecund legacies of Popper’s philosophy are the exciting challenges posed by the numerous open questions raised by fundamental tensions in his thought, some of which I have tried tosketch in this article.

Acknowledgements

I wish to thank Dr. Paolo Baracchi for his philosophically insightful linguistic revision of the text.

17

References

Albert H. 1972. Konstruktion und Kritik: Ausätze zur Philosophie des kritischen Rationalismus. Hamburg: Hoffmann & Campe.

———. 1975. Transzendentale Träumereien: Karl-Otto Apels Sprachspiele und sein hermeneutischer Gott. Hamburg: Hoffmann & Campe.

———. 1982. Die Wissenschaft und die Fehlbarkeit der Vernunft. Tübingen: Mohr.Apel, K. O. 1975. The problem of philosophical fundamental

grounding in light of a transcendental pragmatic of language. Man and World 8: 239–275.

———. 1988. Diskurs und Verantwortung. München: Suhrkamp.Bartley, W. W., III. 1964. Rationality versus the theory of

rationality. In The critical approach to science and philosophy, edited byM. Bunge. New York: Free Press, pp. 3–31.

———. 1984. The retreat to commitment. Second edition. La Salle, IL: OpenCourt.

Berkson, W., and J. R. Wettersten. 1984. Learning from error: Karl Popper’s psychology of learning. La Salle, IL: Open Court.

Bernstein, E. 1899. Die Voraussetzungen des Sozialismus und die Aufgaben der Sozialdemokratie. Stuttgart: Dietz.

Bloor, D. 1991. Knowledge and social imagery. Second edition. London: Routledge and Kegan Paul.

Buzzoni, M. 1980. Umanesimo e scienze sociali in Popper. Sociologia 14 (3): 49–92.

———. 1981. Popper e l’oggettività delle scienze storiche. Il Contributo 5 (1): 3–20.

———. 1982. Conoscenza e realtà in K. R. Popper.Milano: Franco Angeli.

———. 1987. Gewißheit und Wahrheit bei Popper. In Gewissen und Gewißheit, edited by W. Baumgartner. Würzburg: Königshausen & Neumann, pp. 141–163.

Croce, B. 1938. La storia come pensiero e come azione. Bari: Laterza.Currie, G. 1978. Popper’s evolutionary epistemology: A critique.

Synthese 37: 413–431.Gadamer, H.-G. 1986. Wahrheit und Methode: Grundzüge einer philosophischen

Hermeneutik. Fifth edition. Tübingen: Mohr.Gethmann, C. F.., and R. Hegselmann, 1977. Das Problem der

18

Begründung zwischen Dezisionismus und Fundamentalismus. Zeitschrift für allgemeine Wissenschaftstheorie 8: 342–368.

Fuller, S. 2004. Kuhn vs. Popper: The struggle for the soul of science. New York:Columbia University Press.

Habermas, J. 1983. Moralbewußtsein und Kommunikatives Handeln. München: Suhrkamp.

———. 1984. Vorstudien und Ergänzungen zur Theorie des kommunikativen Handelns, München: Suhrkamp.

Hacohen, M. H. 2000. Karl Popper—The formative years, 1902–1945: Politics and philosophy in interwar Vienna. Cambridge: Cambridge University Press.

Jarvie, I. C. 2001. The republic of science: The emergence of Popper’s social view of science 1935–1945. Amsterdam: Rodopi.

Longino, H. E. 1990. Science as social knowledge. Princeton, NJ: Princeton University Press.

Miller, D. 1994. Critical rationalism. La Salle, IL: Open Court.———. 2006. Out of error: Further essays on critical rationalism. Aldershot:

Ashgate.Musgrave, A. 1999. Essays on realism and rationalism. Amsterdam: Rodopi.

Popper, K. R. 1945. The open society and its enemies. Two vols. London: Routledge and Kegan Paul.

———. 1957. The poverty of historicism. London: Routledge.

———. 1963. Conjectures and refutations: The growth of scientific knowledge. London:Routledge and Kegan Paul.

———. 1968. The logic of scientific discovery. Second edition. London: Hutchinson.

———. 1972. Objective knowledge: An evolutionary approach. Oxford: Clarendon Press.

———. 1974a. Intellectual autobiography. In The philosophy of Karl Popper, edited by P. A. Schilpp. La Salle, IL: Open Court, pp. 3–181.

———. 1974b. Replies to my critics. In The philosophy of Karl Popper, edited by P. A. Schilpp. La Salle, IL: Open Court, pp. 961–1197.

———. 1976. A note on verisimilitude. British Journal for the Philosophy of Science 27: 147–159.

Popper, K. R., and J. C. Eccles. 1977. The self and its brain: An argument for interactionism. Berlin: Springer.

Popper, K. R., and F. Kreuzer. 1982. Offene Gesellschaft—offenes Universum. Wien: Franz Deuticke.

19

Putnam, H. 1981. Reason, truth and history. Cambridge: Cambridge University Press.

Radnitzky, G. 1982a. Popper as a turning point in the philosophy of science: Beyond foundationalism and relativism. In In pursuit of truth: Essays in honour of Karl Popper’s 80th birthday, edited by A. Levinson. Brighton: Harvester Press, 64–80.

———. 1982b. Knowing and guessing: If knowledge is conjectural, canwe speak of cognitive progress? On persistent misreadings of Popper’s work. Zeitschrift für allgemeine Wissenschaftstheorie 13: 110–121.

Shearmur, J. 1996. The political thought of Karl Popper. London: Routledge.Skolimowski, H. 1974. Karl Popper and the objectivity of

scientific knowledge. In The philosophy of Karl Popper, edited by P. A. Schilpp. La Salle, IL: Open Court, pp. 483–508.

Watkins, J. W. N. 1969. Comprehensively critical rationalism. Philosophy 44: 57–62.

Wettersten, J. R. 1985. The road through Wurzburg, Vienna and Gottingen. Philosophy of the Social Sciences 15: 487–506.

———. 1992. The roots of critical rationalism. Amsterdam: Rodopi.———. 2005. New insights on young Popper. Journal of the History of Ideas

66: 603–631.———. 2006. How do institutions steer events? An inquiry into the limits and possibilities

of rational thought and action. Aldershot: Ashgate.

20

Notes

21

i Some authors who stressed Popper’s antifoundationalism arecited both in Gattei’s book and in the other works with which weare concerned here; to the list one should add at least Radnitzky(1982a and 1982b), because, to my knowledge, he was the first todevelop this interpretation systematically.ii Skolimowski (1974), 495. I myself have argued at length for adistinction in three phases similar to Jarvie’s, not only regarding the development of Popper’s theory of knowledge (Buzzoni1982 and 1987), but also regarding the development of his thought on the social sciences (Buzzoni 1980) and history (Buzzoni 1981). Today, after the publication of very important works on the early Popper (such as Berkson and Wettersten 1984; Wettersten 1985 and 1992; Hacohen 2000), I would of course add a pre-critical period.