This article describes abductions as special patterns of inference to the best explanation whose structure determines a particularly promising abductive conjecture and thus serves as an abductive search strategy. A classification of different patterns of abduction is provided which intends to be as complete as possible. An important distinction is that between selective abductions, which choose an optimal candidate from given multitude of possible explanations, and creative abductions, which introduce new theoretical models or concepts. While selective abduction has dominated the (...) literature, creative abductions are rarely discussed, although they are essential in science. The article introduces several kinds of creative abductions, such as theoretical model abduction, common cause abduction and statistical factor analysis, and illustrates them by various real case examples. It is suggested to demarcate scientifically fruitful abductions from purely speculative abductions by the criterion of causal unification. (shrink)

Schurz draws on modern alethic- deontic predicate logic to address the venerable yet enduring problem of whether what ought to be can be derived from what is. After two extensive introductory chapters supplying the background in philosophy and logic to readers unfamiliar with it, he examines such dimensions as the logical explication of Hume's thesis, the special Hume thesis, weakened versions of it, generalizations, some applications to ethical arguments, problems of identity and existence, whether there are analytic bridge principles, and (...) whether they are scientifically justifiable. The inquiry is expanded from Part II of his 1989 Relevant Deduction in Science and Ethics with a Case Study of the Is-Ought Problem. No index. Annotation copyrighted by Book News, Inc., Portland, OR. (shrink)

The basic theory of scientific understanding presented in Sections 1–2 exploits three main ideas.First, that to understand a phenomenonP (for a given agent) is to be able to fitP into the cognitive background corpusC (of the agent).Second, that to fitP intoC is to connectP with parts ofC (via arguments in a very broad sense) such that the unification ofC increases.Third, that the cognitive changes involved in unification can be treated as sequences of shifts of phenomena inC. How the theory fits (...) typical examples of understanding and how it excludes spurious unifications is explained in detail. Section 3 gives a formal description of the structure of cognitive corpuses which contain descriptive as well as inferential components. The theory of unification is then refined in the light of so called puzzling phenomena, to enable important distinctions, such as that between consonant and dissonant understanding. In Section 4, the refined theory is applied to several examples, among them a case study of the development of the atomic model. The final part contains a classification of kinds of understanding and a discussion of the relation between understanding and explanation. (shrink)

Normic laws have the form "if A, then normally B." They are omnipresent in everyday life and non-physical 'life' sciences such as biology, psychology, social sciences, and humanities. They differ significantly from ceteris-paribus laws in physics. While several authors have doubted that normic laws are genuine laws at all, others have argued that normic laws express a certain kind of prototypical normality which is independent of statistical majority. This paper presents a foundation for normic laws which is based on generalized (...) evolution theory and explains their omnipresence, lawlikeness, and reliability. It is argued that the fact that normic laws are a product of evolution must establish a systematic connection between prototypical and statistical normality. (shrink)

The background of this paper (section 1) consists in a new account to foundation‐theoretic epistemology characterized by two features: (i) All beliefs are to be justified by deductive, inductive or abductive inferences from a minimalistic class of unproblematic (introspective or analytic) basic beliefs. (ii) Higher‐order justifications for these inferences are given by means of the novel method of optimality justifications. Optimality justifications are a new tool for epistemology (section 2). An optimality justification does not attempt todemonstratethat a cognitive method is (...) reliable (which is impossible), but pursues the more modest goal of demonstrating that the method isoptimalamong all accessible alternative methods for the given epistemic goal. The reasoning from the established optimality of a method to the acceptability of a particular belief generated by the method is accomplished by so‐called optimality principles. In sections 3–5, the method of optimality justifications is carried out in detail for three fundamental problems: justifying induction, logic, and theory‐generating abduction. (shrink)

Starting from a brief recapitulation of the contemporary debate on scientific realism, this paper argues for the following thesis : Assume a theory T has been empirically successful in a domain of application A, but was superseded later on by a superior theory T * , which was likewise successful in A but has an arbitrarily different theoretical superstructure. Then under natural conditions T contains certain theoretical expressions, which yielded T's empirical success, such that these T-expressions correspond (in A) to (...) certain theoretical expressions of T * , and given T * is true, they refer indirectly to the entities denoted by these expressions of T * . The thesis is first motivated by a study of the phlogiston–oxygen example. Then the thesis is proved in the form of a logical theorem , and illustrated by further examples. The final sections explain how the correspondence theorem justifies scientific realism and work out the advantages of the suggested account. Introduction: Pessimistic Meta-induction vs. Structural Correspondence The Case of the Phlogiston Theory Steps Towards a Systematic Correspondence Theorem The Correspondence Theorem and Its Ontological Interpretation Further Historical Applications Discussion of the Correspondence Theorem: Objections and Replies Consequences for Scientific Realism and Comparison with Other Positions 7.1 Comparison with constructive empiricism 7.2 Major difference from standard scientific realism 7.3 From minimal realism and correspondence to scientific realism 7.4 Comparison with particular realistic positions CiteULike Connotea Del.icio.us What's this? (shrink)

Like scientific theories, metaphysical theories can and should be justified by the inference of creative abduction. Two rationality conditions are proposed that distinguish scientific from speculative abductions: achievement of unification and independent testability. Particularly important in science is common cause abduction. The justification of metaphysical realism is structurally similar to scientific abductions: external objects are justified as common causes of perceptual experiences. While the reliability of common cause abduction is entailed by a principle of causality, the latter principle has an (...) abductive justification based on statistical phenomena. (shrink)

, Pietroski and Rey ([1995]) suggested a reconstruction of ceteris paribus (CP)-laws, which — as they claim — saves CP-laws from vacuity. This discussion note is intended to show that, although Pietroski and Rey's reconstruction is an improvement in comparison to previous suggestions, it cannot avoid the result that CP-laws are almost vacuous. It is proved that if Cx is an arbitrary (nomological) event-type which has independently identifiable deterministic causes, then for every other (nomological) event-type Ax which is not strictly (...) connected with Cx or with ¬Cx, ‘CP if Ax then Cx’ satisfies the conditions of Pietroski and Rey for CP-laws. It is also shown that Pietroski and Rey's reconstruction presupposes the assumption of determinism. The conclusion points towards some alternatives to Piectroski and Rey's reconstruction. (shrink)

The article outlines the Multiple-Field-Approach ("Mehr-Felder-Ansatz") in Gestalt Theoretical Psychotherapy and in psychotherapy in general. This Gestalt theory based approach deals 1) with the conditions under which a secondary phenomenal field (containing a secondary phenomenal ego and a secondary phenomenal environment) segregates within the primary phenomenal field, 2) with the dynamic field interaction between primary and secondary field and their role in psychotherapy, 3) with psychotherapeutic techniques favouring the segregation and favouring the dissolution of a secondary field . Some of (...) these phenomena have been discussed as mind-wandering, daydreaming, or - in a pathological context - as dissociation. But it seems that the Gestalt psychological approach presented in this paper has to offer a more promising framework for these phenomena and their dynamics. (shrink)

Jäger, G., Fixed points in Peano arithmetic with ordinals, Annals of Pure and Applied Logic 60 119-132. This paper deals with some proof-theoretic aspects of fixed point theories over Peano arithmetic with ordinals. It studies three such theories which differ in the principles which are available for induction on the natural numbers and ordinals. The main result states that there is a natural theory in this framework which is a conservative extension of Peano arithmeti.

Many of the things we do, we do together with other people. Think of carpooling and playing tennis. In the past two or three decades it has become increasingly popular to analyze such collective actions in terms of collective intentions. This volume brings together ten new philosophical essays that address issues such as how individuals succeed in maintaining coordination throughout the performance of a collective action, whether groups can actually believe propositions or whether they merely accept them, and what kind (...) of evidence, if any, disciplines such as cognitive science and semantics provide in support of irreducibly collective states.The theories of the Big Four of collective intentionality -- Michael Bratman, Raimo Tuomela, John Searle, and Margaret Gilbert -- and the Big Five of Social Ontology -- which in addition to the Big Four includes Philip Pettit -- play a central role in almost all of these essays. Drawing on insights from a wide range of disciplines including dynamical systems theory, economics, and psychology, the contributors develop existing theories, criticize them, or provide alternatives to them.Several essays challenge the idea that there is a straightforward dichotomy between individual and collective level rationality, and explore the interplay between these levels in order to shed new light on the alleged discontinuities between them. These contributions make abundantly clear that it is no longer an option simply to juxtapose analyses of individual and collective level phenomena and maintain that there is a discrepancy. Some go as far as arguing that on closer inspection the alleged discontinuities dissolve. (shrink)

The “return of the state” as an economic actor has left scholars at a lack of theoretical tools to capture the characteristics of state-dominated business systems. This is reflected in the fact that any type of state intervention in the economy is too easily qualified as a sign of “authoritarian capitalism,” which has led scholars to lump together countries as diverse as China, Singapore, and Norway under that heading. Rather than considering any type of state intervention in the economy as (...) authoritarian, we propose a more sophisticated conceptualization, which distinguishes two boundaries between the public and the private domains and conceives of the “return of the state” as the erosion of one or both of them. This conceptualization allows us to clearly distinguish a shift from an ideal-typical market-based “regulatory capitalism” to “state capitalism” or “authoritarian capitalism,” respectively. We use interview data with business leaders in an extreme case of the return of the state to identify the nature of the mechanisms by which an authoritarian government erodes these private-public divides. We argue that a focus on these constitutive mechanisms of the erosion of private-public divides allows us to define “authoritarian capitalism” in a way that makes it a useful tool to understand contexts beyond the Chinese case in which it first emerged. (shrink)

The universal optimality theorem for metainduction works for epistemic agents faced with a choice among finitely many prediction methods. Eckhart Arnold and Tom Sterkenburg objected that it breaks...

Two key ideas of scientific explanation - explanations as causal information and explanation as unification - have frequently been set into mutual opposition. This paper proposes a "dialectical solution" to this conflict, by arguing that causal explanations are preferable to non-causal explanations because they lead to a higher degree of unification at the level of the explanation of statistical regularities. The core axioms of the theory of causal nets are justified because they give the best if not the only unifying (...) explanation of two statistical phenomena: screening off and linking up. Alternative explanation attempts are discussed and it is shown why they don't work. It is demonstrated that not the core of TC but extended versions of TC have empirical content, by means of which they can generate independently testable predictions. (shrink)

The goal of this paper is to answer the following question: Does it make sense to speak of thought experiments not only in physics, but also in mathematics, to refer to an authentic type of activity? One may hesitate because mathematics as such is the exercise of reasoning par excellence, an activity where experience does not seem to play an important role. After reviewing some results of the research on thought experiments in the natural sciences, we turn our attention to (...) experiments and thought experiments in mathematics, especially in fundamental mathematics, and investigate what thought experiments can teach us there. If we accept the principle that mathematical practice can sometimes be best described by a pragmatist approach where the concept of experience in mathematics is considered from a new perspective, thought experiments can in some cases be a useful instrument different from both ‘mathematical experiments’ and ‘formal’ proofs: they are mathematical experiments using deviant methods. (shrink)

Dieser Beitrag erörtert die „übersinnlichen Erkenntnisse“ von Rudolf Steiner zum Thema der Beziehungen von Jesus zu den Essenern. Steiner beschäftigte sich in seinem Vortragszyklus „Das fünfte Evangelium“ mit dieser Frage und präsentierte Erkenntnisse seiner Forschungen aus der Akasha-Chronik. Um die Unabhängigkeit der Akasha-Forschungen von Steiner herauszufiltern, stellt der Autor die Forschungen der Theosophin Blavatsky den Erkenntnissen von Steiner gegenüber. Die Gegenüberstellung verfolgt das Ziel, die Grenzen und Möglichkeiten der Akasha-Forschungen Steiners zu erkunden. Die Arbeit zeigt, dass das fünfte Evangelium von (...) Steiner einige Grundaussagen über die Beziehung von Jesus zu den Essenern enthält, die man bereits bei Blavatsky in „Isis entschleiert“ findet. Dass Steiner die Forschungen ganz unabhängig von bereits vorhandenen Ergebnissen (von Blavatsky) betrieben hat, ist daher unwahrscheinlich. Steiner berichtet über persönliche Begegnungen von Jesus mit den Essenern, die man nirgendwo sonst in dieser Detailliertheit in der Literatur finden kann, und daher hat er einen zusätzlichen Beitrag zur esoterischen Forschung geliefert, der nicht übersehen werden sollte. Eine These, die sich aus dieser Arbeit ergibt, ist, dass Steiner methodisch sowohl den theosophischen Mediumismus als auch die meditative Schau der Akasha-Chronik, die er als exakter empfand, in seine Forschungen einfließen ließ. (shrink)

In this paper I ponder the moral status of conditional threats, in particular the extent to which a threatened party would be permitted to use (lethal) defensive force. I first investigate a mugger case before turning briefly to the more complicated issue of national defence in the face of an invading army. One should not exaggerate the level of protection people under threat owe their conditioned killers simply because what is extorted is of little value. After all, either the conditional (...) threat is willing to kill for something she has no claim on at all, or, if she has a just claim on it - or good reason to believe that she has - she is willing to kill to (re)acquire something of not much worth. In both cases the moral culpability of the conditional threat could be seen as reducing her claim on protection from harm. (shrink)

This paper describes the development of theories of scientific explanation since Hempel's earliest models in the 1940ies. It focuses on deductive and probabilistic whyexplanations and their main problems: lawlikeness, explanation-prediction asymmetries, causality, deductive and probabilistic relevance, maximal specifity and homogenity, the height of the probability value. For all of these topic the paper explains the most important approaches as well as their criticism, including the author's own accounts. Three main theses of this paper are: (1) Both deductive and probabilistic explanations (...) are important in science, not reducible to each other. (2) One must distinguish between (cause giving) explanations and (reason giving) justifications and predictions. (3) The adequacy of deductive as well as probabilistic explanations is relative to a pragmatically given background knowledge-which does not exclude, however, the possibility of purely semantic models. (shrink)

In the first part of my paper I discuss eight arguments in favour of the theory-dependence of observation: realistic content, guidance function of theories, perception as cognitive construction, expectation-dependence of perception, theory-dependence of scientific data, continuity between observational and theoretical concepts, language-dependence, and meaning holism. I argue that although these arguments make correct points, they do not exclude the existence of observations that are weakly theory-neutral in the sense that they don’t depend on acquired background knowledge. In the second part (...) I suggest an experimental method, the method of ostensive learning experiments, by which the degree of theory- and language-independence of a concept can be tested. (shrink)

White (2015) proposes an a priori justification of the reliability of inductive prediction methods based on his thesis of induction-friendliness. It asserts that there are by far more induction-friendly event sequences than induction-unfriendly event sequences. In this paper I contrast White's thesis with the famous no free lunch (NFL) theorem. I explain two versions of this theorem, the strong NFL theorem applying to binary and the weak NFL theorem applying to real-valued predictions. I show that both versions refute the thesis (...) of induction-friendliness. In the conclusion I argue that an a priori justification of the reliability of induction based on a uniform probability distribution over possible event sequences is impossible. In the outlook I consider two alternative approaches: (i) justification externalism and (ii) optimality justifications. (shrink)

Section 10.1 introduces generalized evolution (GE) theory. Here, the three core principles of the theory of evolution − reproduction, variation and selection − are detached from their biological basis, abstracted and extended to other domains, in particular to the domain of cultural evolution (CE). Section 10.2 investigates the ontological foundations of GE and CE theory. They consist in entities and structures that must be realized to get the three modules of evolution running. These entities include self-reproducing systems with variation, and (...) populations of such systems in environments with limited resources. A difference between the reproductive units of BE (biological evolution) and CE consists in the fact that genes act as constructors of evolutionary systems, while memes play the role of modifiers. Section 10.3 is devoted to the abductive justification of GE and CE theory that proceeds in three steps: First, CE theory is justified; second, based on the first step GE theory is abductively justified as the common core of BE and CE; and thirdly, the fruitfulness of GE theory is demonstrated by its applicability to further domains. (shrink)

Introduction : the art of reading -- Adorno and the uncoercive gaze -- Buried possibility : Adorno and Arendt on tradition -- The inheritance of the constellation : Adorno and Hegel -- Judging by refraining from judgment : Adorno's artwork and its Einordnung -- The literary artwork between word and concept : Adorno and Agamben reading Kafka -- The artwork without cardinal direction : notes on orientation in Adorno -- False life, living on : Adorno with Derrida -- Conclusion : (...) a kind of leave-thinking. (shrink)

Summary Giancarlo Trombini presents the continuation of his research on the question of which criteria can be used to assess the progress of therapy in an objectively verifiable way and to make the decision on the completion of therapy. In the first phase of his research, the phenomenological criterion of a qualitative change in the patient’s relations toward the positive and higher complexity was proposed for this purpose. In terms of the working method in analytic therapy, this meant concretely: attention (...) should be paid to what development is shown in the comparison of the relationships that occur in the dream narrative and in the subsequent associations. This criterion was therefore given the name manifest dream/association comparison (MDAC)—comparison between the manifest dream and the subsequent associations. The idea can easily be transferred to those therapy methods, which do not primarily work with reports of dream memories and subsequent associations—also, in other ways of working, it is possible to pay attention, in the way suggested by Trombini, to the qualitative development of the relationships which are thematized by the clients in the course of an hour. To this first criterion, another phenomenological criterion is now added in the present article: that of the “concluding therapeutic turn” (CTT). If the patient’s development reaches this turn in the course of the therapy in one session, this indicates, according to Trombini, that the therapy can soon be concluded. The fulfillment of this criterion can be recognized by the fact that in the sequence of dream narration and subsequent associations in a session, a relational dynamic toward the positive and higher complexity becomes recognizable and that is, at the same time, connected with a reconciliation of the three temporal reference systems (past, present, and future). The achievement of this CTT indicates that the patient is aware of the changes made in therapy and makes it evident to the therapist that the therapy is nearing completion. (shrink)

Suppose two people are about to drown. We are in a position to save only one, so the other will have to die. One of the two has just culpably killed an innocent person, but has no intention of killing anybody else and there is no reason to expect that he will. Everything else being equal, should we give them an equal chance of being saved by flipping a coin? In this paper I argue that we should not. I argue (...) that the implications of a person's moral culpability for (recent or prospective) harm to a particular victim should transfer to other conflict situations in which the wrongdoer might find him or herself. This requires establishing the extent to which a person's contributing to harming another person — and his moral culpability for that harm — impinges on our decision making in situations where it is possible only to assist either the wrongdoer or some other person that is not his victim. (shrink)

v. 1. A-I -- Bd. 2. U-Pū -- Bd. 3. Pra-H.

Agrippa von Nettesheim gilt in der Literatur als Philosoph, der versucht hat, viele verschiedene philosophische Richtungen zu synthetisieren. Sehr interessant ist dabei seine Position zur Transmigration, die bisher in der Literatur nicht intensiver untersucht worden ist. Dieser Aufsatz geht der Frage nach der Position von Agrippa in Bezug auf die Transmigration nach. Durch die sehr verstreuten und widersprüchlichen Zitate von Agrippa zu diesem Thema gibt es bisher keine eindeutigen Aussagen in der Sekundärliteratur dazu, ob Agrippa die Lehre der Transmigration vertreten (...) hat oder nicht. Die These dieses Aufsatzes ist, dass Agrippa an Transmigration glaubte und am Ende steht diese Erkenntnis in Verbindung mit einer etwas eigenen Christologie, die man bis dahin so nicht findet. Agrippa glaubte, dass Christus die Lehre der Wiedervergeltung gelehrt hat, doch im Gegensatz zu den Gnostikern war Jesus für ihn nicht Mensch, sondern Sohn Gottes. Agrippa hat selbst darauf hingewiesen, dass nur der „einsichtige Leser“ seine verdeckte Methode entschlüsseln kann. Gerade bei der Transmigration hat Agrippa absichtlich diese verdeckte Methode eingesetzt, um sich vor der Verfolgung durch kirchliche Autoritäten zu schützen. (shrink)

This paper contributes to the clarification of the concept of “typicality” discussed in contemporary philosophy of physics by conceiving the nomological status of a typical behaviour such as that expressed in the Second Law of Thermodynamics as a “minutis rectis law”. A brief sketch of the discovery of “typicality” shows that there were ideas of typical behaviour not only in physics but also in sociology. On this basis and in analogy to the Second Law of Thermodynamics, it is shown that (...) the nomological status of sociological laws such as Gresham’s Law can also be conceived as “minutis rectis laws”. (shrink)

Mind-wandering is often seen as the result of a certain attention behavior or even an attention deficit. However, Gestalt psychological research points to other explanations: The phenomena referred to as “mind-wandering” can be understood as a reorganization of the total phenomenal field of perception and experience as a result of experiencing serious discrepancies in this field (“non-Prägnanz” or “Imprägnanzen” in Gestalt psychological terminology). If the “non-Prägnanz” in the field is strong enough, the related facts and events are experienced as not (...) being compatible in a single common field. As a consequence, the field of perception and experience is split into two or more fields, each comprising its own phenomenal ego with its own phenomenal world. This approach allows the identification of certain rules for the occurrence of these phenomena and an informed handling of them. The paper introduces this Gestalt psychological multiple-field approach and discusses its conditions, implications, and potential applications. Examples from Gestalt theoretical psychotherapy, in the context of which this approach was developed in a differentiated way, and from other areas of application, serve as illustrations. (shrink)

This open access book examines the many contributions of Paul Lorenzen, an outstanding philosopher from the latter half of the 20th century. It features papers focused on integrating Lorenzen's original approach into the history of logic and mathematics. The papers also explore how practitioners can implement Lorenzen’s systematical ideas in today’s debates on proof-theoretic semantics, databank management, and stochastics. Coverage details key contributions of Lorenzen to constructive mathematics, Lorenzen’s work on lattice-groups and divisibility theory, and modern set theory and Lorenzen’s (...) critique of actual infinity. The contributors also look at the main problem of Grundlagenforschung and Lorenzen’s consistency proof and Hilbert’s larger program. In addition, the papers offer a constructive examination of a Russell-style Ramified Type Theory and a way out of the circularity puzzle within the operative justification of logic and mathematics. Paul Lorenzen's name is associated with the Erlangen School of Methodical Constructivism, of which the approach in linguistic philosophy and philosophy of science determined philosophical discussions especially in Germany in the 1960s and 1970s. This volume features 10 papers from a meeting that took place at the University of Konstanz. (shrink)

Reality and Humean Supervenience confronts the reader with central aspects in the philosophy of David Lewis, whose work in ontology, metaphysics, logic, probability, philosophy of mind, and language articulates a unique and systematic foundation for modern physicalism.

Organisms are self-producing and self-maintaining, or autopoietic systems. Therefore, the course of evolution and adaptation of an organism is strongly determined by its own internal properties, whatever role external selection may play. The internal properties may either act as constraints that preclude certain changes or they open new pathways: the organism canalizes its own evolution. As an example the evolution of feeding mechanisms in salamanders, especially in the lungless salamanders of the family Plethodontidae, is discussed. In this family a large (...) variety of different feeding mechanisms is found. The authors reconstruct this evolutionary process as a series of bifurcation points of either constraints or opportunities forming a sequence of preconditions for the formation of a high-speed projectile tongue characteristic of tropical salamanders. Furthermore, it is shown how parallel evolution of seemingly unrelated domains within an organism such as respiratory physiology, life history biology and pattern of ontogeny has rather direct relevance to the feeding biology, thus demonstrating that organisms always evolve as wholes. (shrink)

Two conditions guiding permissible use of force in self-defence are proportionality and success. According to the proportionality condition the means used to prevent an attack can be permissible only if they are proportional to the interest at stake.1 According to the success condition, otherwise impermissible acts can be justified under the right to self-defence only if they are likely to succeed in preventing the perceived threat.2 These requirements should not always be interpreted narrowly. Sometimes people are permitted to kill culpable (...) aggressors in order to avoid a non-lethal harm. Sometimes people are permitted to take up arms to defend themselves against culpable aggressors they have little or no hope of .. (shrink)

A riddle in the ethics of war concerns whether lethal defensive force may be justifiably used against aggressing soldiers who are morally innocent.

In Sect. 1 it is argued that systems of logic are exceptional, but not a priori necessary. Logics are exceptional because they can neither be demonstrated as valid nor be confirmed by observation without entering a circle, and their motivation based on intuition is unreliable. On the other hand, logics do not express a priori necessities of thinking because alternative non-classical logics have been developed. Section 2 reflects the controversies about four major kinds of non-classical logics—multi-valued, intuitionistic, paraconsistent and quantum (...) logics. Its purpose is to show that there is no particular domain or reason that demands the use of a non-classical logic; the particular reasons given for the non-classical logic can also be handled within classical logic. The result of Sect. 2 is substantiated in Sect. 3, where it is shown (referring to other work) that all four kinds of non-classical logics can be translated into classical logic in a meaning-preserving way. Based on this fact a justification of classical logic is developed in Sect. 4 that is based on its representational optimality. It is pointed out that not many but a few non-classical logics can be likewise representationally optimal. However, the situation is not symmetric: classical logic has ceteris paribus advantages as a unifying metalogic, while non-classical logics can have local simplicity advantages. (shrink)