关于存在预设失效的语义学探究

存在预设在经典逻辑中有着重要的地位。存在预设失效了的逻辑系统就会成为一种自由逻辑系统,不得不面对空名与真值间隙问题。本文基于这些自由逻辑系统讨论了如何为存在预设失效提供一个合适的语义解释:首先通过语义预设的概念来定义存在预设、将真值间隙定义为二值原则失效,而后比较了为真值间隙赋值的不同方案,最终在虚构主义的立场上指出,超赋值语义学在把空名看作虚构对象名称的同时保留了逻辑真,是较为理想的语义解释。     

弗雷格坍塌、弹弓论证与共指替换——评颜青山对句子指称的分析

弗雷格所持句子指称真值的主张导致"弗雷格坍塌",即所有真句子指称真,所有假句子指称假。这一点为丘奇、哥德尔等人的"弹弓论证"所证明。要避免这种后果,应当审查弗雷格的两个预设:限定摹状词是专名的观点和组合性原则。罗素通过摹状词理论消除了坍塌,但其理论存在基本缺陷。颜青山试图表明弗雷格误用了组合性原则并得出句子指称事态而非真值,但他的论证是不成功的。     

情感主义的语义表述

情感主义(emotivism)是元伦理学的重要学说之一。艾耶尔是这一学说的主要代表人物。参照斯图尔加(D.Stoljar)的观点①,可以将艾耶尔的情感主义概括为语义和语用两个基本论点:语义论点:道德语句缺乏真值条件,不能为真或为假。语用论点:道德语句的作用是表达情感,以及劝说人们以某种方式行动。(Stoljar,p.81)然而,这一版本的情感主义面临两方面的问题:(1)弗雷格-吉奇问题:一个缺乏真值条件而只有     

一个关于专名指称存在预设的形式刻画

目前关于预设的真值语义学研究主要是各种三值语义。这看起来有自然的一面,但其实有一个严重的误区,将"无定义"也看成一个与预设原句真值处于同一层面的真值,混淆了对象语言与元语言的区分。预设句与原句是不同层次的句子。本文试以专名指称存在预设为例,通过部分模型以及在此之上的同底扩张模型方法构造了复合模型,给出了一个既保证不同语言层次的区分又可以跨层次统一谈论原句和预设句关系的形式语义。通过这个语义,揭示了预设句与原句的2//[2]+[0]式的真值结构,使得通常情况下关于预设的默认得到形式上的刻画和呈现。     

新弗雷格主义对涵义的认知解释

对弗雷格式涵义的描述主义解释传统受到了克里普克和直接指称论者的深入批评。新弗雷格主义者坚持涵义的不可或缺性而建议放弃描述主义。新弗雷格主义者对弗雷格式涵义的实质内容的阐发可以解读成三种进路：一是把涵义解释成从物的思考方式或心理呈现模式;二是把涵义解释成证实性知识或作为证据的概念;三是把涵义解释成动态的信息体或文件系统。这三种理解都强调了弗雷格式涵义的认知功能,从而显示出涵义概念的语义解释和认知解释之间的紧张,以及涵义概念的内在不融贯性。二维语义学承接新弗雷格主义的立场把弗雷格式涵义拆分成认知内涵和真值条件内涵两个维度,涵义的认知层面是弗雷格式涵义的主要特征。     

语义预设的界定与鉴别

预设和蕴涵的鉴别是预设的语义分析重点研究的内容。现有的研究过分强调预设的真值定义和否定测试法会导致对语义预设的片面理解。因此,有必要对语义预设的界定和已有的鉴别方法进行分析,并根据预设是语义和语用的接口的语言事实,结合语用来弥补预设语义分析的缺陷,以便更准确地鉴别语义预设。     

非严格弗雷格自由逻辑

莱曼(S.Lehmann)的1994年的论文从三值逻辑角度处理语言中的空词项。弗雷格认为句子的所指是真值,包含空词项的句子缺乏所指,而只有涵义,那么这样的句子不真也不假。莱曼的文章刻画了弗雷格这一思想,但有两点不尽人意之处:其一、对量词进行特殊处理,使得量词公式是二值的;其二,把包含空词项的复合句一概归于第三值。针对上述两点,本文以一度衍推系统为基础,在语义上,以偏解释函数为基础构造了一个非严格弗雷格中性自由逻辑表列系统,使得量词公式是三值的,同时使得一部分包含空词项的复合公式或真或假。     

概念语义与弗雷格迷题消解

弗雷格因同一替换律讨论而提出了涵义与指称的理论,这个理论后来引出了弗雷格迷题。弗雷格迷题的形成有多方原因,直接指称论对弗雷格理论批评是主要原因之一,以至于可以说,这是产生于直接指称论哲学立场的迷题。尽管如此,弗雷格理论确有不足。最重要的是,弗雷格理论只有关于涵义与指称的理论,即只有语言层面的理论,而缺少认知层面的理论。这个不足使得在弗雷格理论基础上解决同一替换律问题难有令人满意的结果,让"迷题"多添了几分"迷"的色彩。这里将给出一个新的方案:在弗雷格理论的基础上,增加有关概念的理论,以概念和内涵、涵义等这些概念的形式刻画为中心,建立可以消解弗雷格迷题的形式语义学,即概念语义。通过概念语义可以在不同层次上对弗雷格迷题的消解给出统一回答。     

规约隐涵、一般性会话隐涵与预设范畴的扩展

本文在考察规约隐涵、一般性会话隐涵等概念及其相互关系的基础上,提出了语句的非真值条件意义的再处理设想,即缩小"隐涵"范畴,扩展"语义预设"范畴。具体言之:解散隐涵集合体,只保留特殊会话隐涵,即"隐涵"等于"特殊会话隐涵";取消"规约隐涵"概念,把它归入语义预设(强规约隐涵归入典型语义预设,弱规约隐涵归入非典型语义预设);取消"一般性会话隐涵"概念,把它归入非典型语义预设。"预设"概念的外延扩展后,其分类系统则为:预设分为语义预设与语用预设;语义预设再分为典型语义预设与非典型语义预设;语用预设再分为命题内容条件语用预设、预备性条件语用预设、真诚性条件语用预设和实质性条件语用预设。     

“预设”研究

众所周知,一系列非标准逻辑分支不断脱颖而出,成为上世纪末以来逻辑学发展的一个重要特征;在诸多非标准逻辑分支中,预设逻辑已愈益为国内外研究者所关注。最早使用预设(Presupposition)一词的是弗雷格和罗素,第一个赋予这一概念以科学含义的要算英国学者斯特劳森。近几十年来,国外,对预设的研究更加深入、力求形式化。西方逻辑学家认为,预设至少可以分为三种:语义预设、语用预设和语境预设。所谓语义预设,就是一般所讲的预设,又叫逻辑预设。一般都同意逻辑学家斯特劳森的定义:“一个命题S预设一个命题S′当且仅当S′是S有真假值的必要条件。”(参览P.F.Strawson《Introduction to Logieal theory》1952年伦敦版P.175)例如,当今知名     

Frege on the psychological significance of definitions

Conclusion In contemporary work, the distinction between the proposition expressed by a sentence and its psychological significance is usually motivated by a familiar kind of counterfactual argument; and the discussion of these issues usually centers around the role of external factors in determining the meaning of our words. My primary goal in this paper has been to show that a similar, though not identical, distinction between two aspects of meaning can be developed entirely on the basis of considerations internal to language users — their cognitive limitations. To make this point, I have focused on symbols introduced through stipulative definitions. In a language containing such symbols, certain expressions and their definitional reductions will seem to differ in psychological significance for creatures with limited intellects, and so in any aspect of meaning that is supposed to correlate with psychological significance; but it seems also that there is some important aspect of meaning that they share.I have argued that a distinction in meaning like this — between sense and psychological significance — should be drawn even in the kind of languages of most concern to Frege, and that his failure to do so led to tensions in his thought. Of course, this observation only touches on the many issues involved in interpreting Frege's theory of definition more generally. I have not tried to describe here, for example, the ways in which the weak interpretation of fruitfulness might interact with the more robust interpretation mentioned earlier; I have only mentioned Frege's view on explicative definitions and the paradox of analysis, and failed even to mention either his treatment of contextual definition, or his peculiar objections to conditional definitions. I do want to emphasize, however, that the distinction drawn here is not simply a matter of Frege scholarship, but that it has some contemporary relevance as well. As we have seen, Frege's semantic goals often coincide with our own; and a number of contemporary writers are explicitly concerned, like Frege, to construct a semantic theory that is able to account for differences in meaning among logically equivalent expressions. Any such theorist should recognize a distinction like that drawn here between sense and psychological significance, and should avoid subjecting an account of one notion to constraints appropriate only for the other.     

Understanding Frege’s notion of presupposition

Why did Frege offer only proper names as examples of presupposition triggers? Some scholars claim that Frege simply did not care about the full range of presuppositional phenomena. This paper argues, in contrast, that he had good reasons for employing an extremely narrow notion of ‘Voraussetzung’. On Frege’s view, many devices that are now construed as presupposition triggers either express several thoughts at once or merely ‘illuminate’ a thought in a particular way. Fregean presuppositions, in contrast, are essentially tied to names.

     

A heterodox defense of the actualist higher-order thought theory

I defend the actualist higher-order thought theory against four objections. The first objection contends that the theory is circular. The second one contends that the theory is unable to account for the alleged epistemic position we are in with respect to our own conscious mental states. The third one contends that the theory is unable to account for the evidence we have for the proposition that all conscious mental states are represented. The fourth one contends that the theory does not accommodate the intimacy we have with our own conscious mental states. To some extent, my defense will be heterodox, in the sense that I will show that some objections are satisfactorily answerable even if we concede to the objectors a point that higher-order theorists do not seem to be willing to concede, that is, that the theory is the result of conceptual analysis.

     

Accommodating Presuppositions

In this paper I elaborate on previous criticisms of the influential Stalnakerian account of presuppositions, pointing out that the well-known practice of informative presupposition puts heavy strain on Stalnaker’s pragmatic characterization of the phenomenon of presupposition, in particular of the triggering of presuppositions. Stalnaker has replied to previous criticisms by relying on the well-taken point that we should take into account the time at which presupposition-requirements are to be computed. In defense of a different, ‘semantic’ (in a sense) account of the phenomenon of presupposition, I argue that that point does not suffice to rescue the Stalnakerian proposal, and I portray Lewisian ‘accommodation’ as one way in which speakers adjust themselves to one another in the course of conversation.     

TRUTH AND METATHEORY IN FREGE

In this paper it is contended, against a challenging recent interpretation of Frege, that Frege should be credited with the first semi-rigorous formulation of semantic theory. It is argued that the considerations advanced against this contention suffer from two kinds of error. The first involves the attribution to Frege of a sceptical attitude towards the truth-predicate. The second involves the sort of justification which these arguments assume a classical semantic theory attempts to provide. Finally, it is shown that Frege was in fact mindful of the need for the relevant sort of justification.     

The Contents of Perception and the Contents of Emotion

Several philosophers think there are important analogies between emotions and perceptual states. Furthermore, considerations about the rational assessibility of emotions have led philosophers—in some cases, the very same philosophers—to think that the content of emotions must be propositional content. If one finds it plausible that perceptual states have propositional contents, then there is no obvious tension between these views. However, this view of perception has recently been attacked by philosophers who hold that the content of perception is object‐like. I shall argue for a view about the content of emotions and perceptual states which will enable us to hold both that emotional content is analogous to perceptual content and that both emotions and perceptual states can have propositional contents. This will involve arguing for a pluralist view of perceptual content, on which perceptual states can have both contents which are proposition‐like and contents which are object‐like. I shall also address two significant objections to the claim that emotions can have proposition‐like contents. Meeting one of these objections will involve taking on a further commitment: the pluralist account of perceptual content will have to be one on which the contents of perception can be non‐conceptual.     

The Processing Costs of Presupposition Accommodation

The present study investigates the processing of presupposition accommodation. In particular, it concerns the processing costs and the time-course of accommodation as compared to presupposition satisfaction. Data collected in a self-paced word-by-word reading times experiment support three results. First, independently on the presupposition trigger in use, accommodation is costlier than satisfaction. Second, presupposition accommodation takes places immediately just as the trigger becomes available and proceeds incrementally during the sentence processing. Third, accommodated information is harder to be recalled. The results offer evidence for the on-line processing of presuppositions and, consistently with the traditional semantic framework, support the idea that, presuppositions are semantic properties encoded in the lexical meaning of the presupposition triggers.     

Some Naturalistic Comments on Frege’s Philosophy of Mathematics

This paper compares Frege’s philosophy of mathematics with a naturalistic and nominalistic philosophy of mathematics developed in Ye (2010a, 2010b, 2010c, 2011), and it defends the latter against the former. The paper focuses on Frege’s account of the applicability of mathematics in the sciences and his conceptual realism. It argues that the naturalistic and nominalistic approach fares better than the Fregean approach in terms of its logical accuracy and clarity in explaining the applicability of mathematics in the sciences, its ability to reveal the real issues in explaining human epistemic and semantic access to objects, its prospect for resolving internal difficulties and developing into a full-fledged theory with rich details, as well its consistency with other areas of our scientific knowledge. Trivial criticisms such as “Frege is against naturalism here and therefore he is wrong” will be avoided as the paper tries to evaluate the two approaches on a neutral ground by focusing on meta-theoretical features such as accuracy, richness of detail, prospects for resolving internal issues, and consistency with other knowledge. The arguments in this paper apply not merely to Frege’s philosophy. They apply as well to all philosophies that accept a Fregean account of the applicability of mathematics or accept conceptual realism. Some of these philosophies profess to endorse naturalism.     

Predication and the Frege–Geach problem

Several philosophers have recently appealed to predication in developing their theories of cognitive representation and propositions. One central point of difference between them is whether they take predication to be forceful or neutral and whether they take the most basic cognitive representational act to be judging or entertaining. Both views are supported by powerful reasons and both face problems. Many think that predication must be forceful if it is to explain representation. However, the standard ways of of implementing the idea give rise to the Frege–Geach problem. Others think that predication must be neutral, if we’re to avoid the Frege–Geach problem. However, it looks like nothing neutral can explain representation. My aim in this paper is to present a third view, one which respects the powerful reasons while avoiding the problems. On this view predication is forceful and can thus explain representation, but the idea is implemented in a novel way, avoiding the Frege–Geach problem. The key is to make sense of the notion of grasping a proposition as an objectual act, where the object is a proposition.