The Logics of Discovery in Popper’s Evolutionary Epistemology

Popper is well known for rejecting a logic of discovery, but he is only justified in rejecting the same type of logic of discovery that is denied by consequentialism. His own account of hypothesis generation, based on a natural selection analogy, involves an error-eliminative logic of discovery and the differences he admits between biological and conceptual evolution suggest an error-corrective logic of discovery. These types of logics of discovery are based on principles of plausibility that are used in the generation as opposed to the preliminary evaluation of hypotheses. The normative relevance of these principles is grounded in the distinction between strategic and definitory rules.

Forcing in Łukasiewicz Predicate Logic

In this paper we study the notion of forcing for Łukasiewicz predicate logic (Ł∀, for short), along the lines of Robinson’s forcing in classical model theory. We deal with both finite and infinite forcing. As regard to the former we prove a Generic Model Theorem for Ł∀, while for the latter, we study the generic and existentially complete standard models of Ł∀. Presented by Jacek Malinowski     

On the role of language in social choice theory

Axiomatic characterization results in social choice theory are usually compared either regarding the normative plausibility or regarding the logical strength of the axioms involved. Here, instead, we propose to compare axiomatizations according to the language used for expressing the axioms. In order to carry out such a comparison, we suggest a formalist approach to axiomatization results which uses a restricted formal logical language to express axioms. Axiomatic characterization results in social choice theory then turn into definability results of formal logic. The advantages of this approach include the possibility of non-axiomatizability results, a distinction between absolute and relative axiomatizations, and the possibility to ask how rich a language needs to be to express certain axioms. We argue for formal minimalism, i.e., for favoring axiomatizations in the weakest language possible.     

Short-term effects of grade retention on the growth rate of Woodcock-Johnson III broad math and reading scores

We investigated the effects of grade retention in first grade on the growth of the Woodcock-Johnson broad mathematics and reading scores over three years using linear growth curve modeling on an academically at-risk sample. A large sample (n = 784) of first grade children who were at risk for retention was initially identified based on low literacy scores. Scores representing propensity for retention were constructed based on 72 variables collected in comprehensive baseline testing in first grade. We closely matched 97 pairs of retained and promoted children based on their propensity scores using optimal matching procedures. This procedure adjusted for baseline differences between the retained and promoted children. We found that grade retention decreased the growth rate of mathematical skills but had no significant effect on reading skills. In addition, several potential moderators of the effect of retention on growth of mathematical and reading skills were identified including limited English language proficiency and children's conduct problems.     

How is God-talk logically possible? A sketch for an argument on the logic of ‘God’

In this paper I want to argue for the optimal way to characterise the logical and semantical behaviour of the singular term ‘God’ used in religious language. The relevance of this enterprise to logical theory is the main focus as well. Doing this presupposes to outline the two rivaling approaches of well-definition of singular terms: Kripke’s (“rigid designators”) and Hintikka’s (“world-lines”). ‘God’ as a “rigid designator” is purified from all real-life-language-games of identification and only spells out a metaphysical tag, which favours the view of “anything goes”. Instead, ‘God’ as a “world-line,” plus two ways of quantification, is much more flexible to theological traditions, teachings of the church, religious practices and personal feelings. Thus, it provides a sufficiently well-defined singular term for the purposes of logical theory. The whole sketch is based on Jaakko Hintikka’s logical ideas, mainly on his responses to different authors in PJH. I have systematically omitted direct references to his texts because I have modified considerably his ideas for my own purposes.     

AI,ME AND LEWIS (ABELIAN IMPLICATION,MATERIAL EQUIVALENCE AND C I LEWIS 1920)

C I Lewis showed up Down Under in 2005, in e-mails initiated by Allen Hazen of Melbourne. Their topic was the system Hazen called FL (a Funny Logic), axiomatized in passing in Lewis 1921. I show that FL is the system MEN of material equivalence with negation. But negation plays no special role in MEN. Symbolizing equivalence with → and defining ∼A inferentially as A→f, the theorems of MEN are just those of the underlying theory ME of pure material equivalence. This accords with the treatment of negation in the Abelian l-group logic A of Meyer and Slaney (Abelian logic. Abstract, Journal of Symbolic Logic 46, 425–426, 1981), which also defines ∼A inferentially with no special conditions on f. The paper then concentrates on the pure implicational part AI of A, the simple logic of Abelian groups. The integers Z were known to be characteristic for AI, with every non-theorem B refutable mod some Zn for finite n. Noted here is that AI is pre-tabular, having the Scroggs property that every proper extension SI of AI, closed under substitution and detachment, has some finite Zn as its characteristic matrix. In particular FL is the extension for which n = 2 (Lewis, The structure of logic and its relation to other systems. The Journal of Philosophy 18, 505–516, 1921; Meyer and Slaney, Abelian logic. Abstract. Journal of Symbolic Logic 46, 425–426, 1981; This is an abstract of the much longer paper finally published in 1989 in G. G. Priest, R. Routley and J. Norman, eds., Paraconsistent logic: essays on the inconsistent, Philosophica Verlag, Munich, pp. 245–288, 1989). Meyer was supported in this work as a Visiting Fellow in the College of Engineering and Computer Science, ANU.     

Multiple Kernel Contraction

This paper focuses on the extension of AGM that allows change for a belief base by a set of sentences instead of a single sentence. In [FH94], Fuhrmann and Hansson presented an axiomatic for Multiple Contraction and a construction based on the AGM Partial Meet Contraction. We propose for their model another way to construct functions: Multiple Kernel Contraction, that is a modification of Kernel Contraction, proposed by Hansson [Han94] to construct classical AGM contractions and belief base contractions. This construction works out the unsolved problem pointed out by Hansson in [Han99, pp. 369]. This revised version was published online in August 2006 with corrections to the Cover Date.     

现象学与逻辑学

无论在胡塞尔思想中还是在海德格尔思想中,现象学与逻辑学的关系都构成一个核心问题。本文首先再现了胡塞尔前后期在此问题上的相关研究,并指出他的超越论逻辑学的要点在于对本质的前逻辑直观,也是最有可能为逻辑学提供哲学支撑的因素。其次,在海德格尔方面,根据律概念成为讨论现象学与逻辑学关系的切入点,由此导出他的“存在理解”、“无蔽”和“自由”的概念解释。他们的共同点在于：把形式逻辑看作陈述逻辑,并试图用前谓词判断的哲学逻辑学来为它奠基。     

Problems and results for logics about imperatives

Deviating from standard possible-worlds semantics, authors belonging to what might be called the ‘imperative tradition’ of deontic logic have proposed a semantics that directly represents norms (or imperatives). The paper examines possible definitions of (monadic) deontic operators in such a semantics and some properties of the resulting logical systems.     

童年期攻击行为发展的追踪研究

本研究采用"班级戏剧问卷"对中部一所小学3、4年级的285名儿童进行了3年追踪调查,研究了3年来儿童的外部攻击和关系攻击发展趋势及其在个体间的差异,并探讨了两类攻击行为发展趋势之间的关系。结果表明:(1)童年中后期外部攻击和关系攻击的变化趋势不显著。并且初始测量的外部攻击水平高的儿童,其关系攻击水平也较高;外部攻击行为变化较快的儿童,其关系攻击变化也比较快。(2)男生的外部攻击水平显著高于女生,而关系攻击的性别差异不显著。四年级关系攻击的上升速度快于三年级;初始为关系攻击较高组相对于较低组,他们的关系攻击随时间的上升速度也比较快。