Many different arguments against the possibility of perfect rationality have appeared in the literature, and these target several different conceptions of perfect rationality. It is not clear how these different conceptions of perfect rationality are related, nor is it clear how the arguments showing their impossibility are related, and it is especially unclear what the impossibility results show when taken together. This paper gives an exposition of the different conceptions of perfect rationality, an the various sorts of argument against them; (...) clarifies which conceptions of perfect rationality are targeted by which arguments; and finally attempts to systematize the results available to date. (shrink)

The relations between rationality and optimization have been widely discussed in the wake of Herbert Simon's work, with the common conclusion that the rationality concept does not imply the optimization principle. The paper is partly concerned with adding evidence for this view, but its main, more challenging objective is to question the converse implication from optimization to rationality, which is accepted even by bounded rationality theorists. We discuss three topics in succession: (1) rationally defensible cyclical choices, (2) the revealed preference (...) theory of optimization, and (3) the infinite regress of optimization. We conclude that (1) and (2) provide evidence only for the weak thesis that rationality does not imply optimization. But (3) is seen to deliver a significant argument for the strong thesis that optimization does not imply rationality. (shrink)

Social science employs teleological explanations which depend upon the rationality principle, according to which people exhibit instrumental rationality. Popper points out that people also exhibit critical rationality, the tendency to stand back from, and to question or criticise, their views. I explain how our critical rationality impugns the explanatory value of the rationality principle and thereby threatens the very possibility of social science. I discuss the relationship between instrumental and critical rationality and show how we can reconcile our critical rationality (...) with the possibility of social science if we invoke Popper’s conception of limited rationality and his indeterminism. (shrink)

The global lockdown following the outbreak of the COVID-19 pandemic is likely to generate all sorts of consequences: psychological, social, economic, and political. To hypothesize about what will emerge from the present situation is at this point both premature and impossible. The impossibility comes primarily from the gravity and vastness of this emergency and from the lack of intellectual resources to deal with the challenge. At the same time, however, the need to get a grasp of the condition in which (...) we have found ourselves is both understandable and irresistible. One way of responding, at least partially, to the demand and its possible consequences may be to refer to the concept of abstract society, an idea formulated 75 years ago by the Austrian-British philosopher Karl Popper. (shrink)

[This is the complete issue of the second issue of Mɛtascience] -/- This second issue of the journal Mεtascience continues the char acterization of this new branch of knowledge that is metasci ence. If it is new, it is not in a radical sense since Mario Bunge practiced it in an exemplary way, since logical positivists were accused of practicing only a mere metascience, since scientists have always practiced it implicitly, and since some philosophers no longer practice philosophy but rather (...) metascience, but without characterizing it or theorizing it, that is, without realizing that they have abandoned one general discourse for another. The novelty therefore lies in this aware ness that a general discourse without philosophy is possible: a scien tific general discourse. The twelve contributions gathered in this volume illustrate the metascientific approach to knowledge of the world as well as to knowledge of knowledge of the world, that is, science. And like Bunge’s project, they are neither part of the analytical movement nor the continental movement in philosophy. We will read here studies about the Bungean system, some applications of Bungean thought, some metascientific contributions, and some reflections around meta science. Among metascientific disciplines, ontology occupies a prominent place in this issue of Mεtascience. Metascience differs from philoso phy in its rejection of the fundamental philosophical distinction be tween appearance and reality. Metascientific ontology therefore does not postulate the existence of any metaphysical reality. But metasci entific ontology, no more than philosophical ontology, is a factual sci ence. The first, because it studies scientific constructs and not concrete objects, the second, because it is interested in transcendent or meta physical objects. (shrink)

Karl Popper’s “Indeterminism in Quantum Physics and in Classical Physics” suffers unjust neglect. He judged determinism false: the future is open. In principle, replacing Laplace's variant of predetermination with predictable predetermination renders “scientific” determinism scientific and so refutable. Popper claimed that he had refuted it. Now a metaphysical system may have an extension—in the mathematical sense—that may render it explanatory and testable. If it exists, then it is not unique but has many alternative extensions. Popper’s proof is then inconclusive.

This paper examines narrativism’s claim that the historical past cannot be known once and for all because it must be continuously re-described from the standpoint of the present. We argue that this claim is based on a non sequitur. We take narrativism’s claim that the past must be re-described continuously from the perspective of the present to be the result of the following train of thought: 1) “all knowledge is conceptually mediated”; 2) “the conceptual framework through which knowledge of reality (...) is mediated changes with every new generation of historians”; therefore (narrativism’s claim) “the historical past changes with every new generation of historians”. The idea of an unchanging past, for the narrativist, requires denying premise 1 (all knowledge is conceptually mediated”) and therefore rests on a problematic commitment to the chimerical notion of the past as it is in-itself, wie es eigentlich gewesen. We argue that the narrativist’s conclusion does not follow unless one adds a further premise, namely 3) “it is not possible to view reality through the categorial framework of historical agents”. If one asserts the possibility of grasping reality through the categorial framework of others, be they contemporary or past agents (as much philosophy of history written in an idealist key does), then one no longer has to accept the narrativist’s inference that since the past cannot be known in-itself or independently of conceptual mediation, then it cannot be known as it always was for the historical agents. Narrativism’s inference that the past cannot be known as it always was does not follow from premises 1 and 2 unless one smuggles in another problematic premise, premise 3. In this paper we defend the claim that the past can be known as it always was (not as it is in-itself) by invoking a different conception of the role of conceptual mediation in historical knowledge, one which assumes the possibility of viewing reality through the categorial framework of others. This notion of the role of conceptual mediation in historical knowledge is prevalent in the idealist tradition but, in the interest of brevity, we will defend this notion of mediacy by specific reference to the idealist philosophy of R.G. Collingwood. (shrink)