Objects and Processes in Mathematical Practice

In this paper it is argued that the fundamental difference of the formal and the informal position in the philosophy of mathematics results from the collision of an object and a process centric perspective towards mathematics. This collision can be overcome by means of dialectical analysis, which shows that both perspectives essentially depend on each other. This is illustrated by the example of mathematical proof and its formal and informal nature. A short overview of the employed materialist dialectical approach is given that rationalises mathematical development as a process of model production. It aims at placing more emphasis on the application aspects of mathematical results. Moreover, it is shown how such production realises subjective capacities as well as objective conditions, where the latter are mediated by mathematical formalism. The approach is further sustained by Polanyi’s theory of problem solving and Stegmaier’s philosophy of orientation. In particular, the tool and application perspective illuminates which role computer-based proofs can play in mathematics.     

论数学中的虚构主义

数学虚构主义是"数学实体不存在、数学中不存在真理、数学在世界的说明和科学事业中可有可无"的一种典型的当代数学反实在论的解释。通过对数学虚构主义的批判性分析,得出"数学虚构主义的反实在论规划整体上并不成功","数学在世界的说明和科学中是至关重要,而非可有可无"、"数学实体确实不存在"和"数学中存在真理,但其本质需进一步研究"的结论。     

Top-Down and Bottom-Up Philosophy of Mathematics

The philosophy of mathematics of the last few decades is commonly distinguished into mainstream and maverick, to which a ‘third way’ has been recently added, the philosophy of mathematical practice. In this paper the limitations of these trends in the philosophy of mathematics are pointed out, and it is argued that they are due to the fact that all of them are based on a top-down approach, that is, an approach which explains the nature of mathematics in terms of some general unproven assumption. As an alternative, a bottom-up approach is proposed, which explains the nature of mathematics in terms of the activity of real individuals and interactions between them. This involves distinguishing between mathematics as a discipline and the mathematics embodied in organisms as a result of biological evolution, which however, while being distinguished, are not opposed. Moreover, it requires a view of mathematical proof, mathematical definition and mathematical objects which is alternative to the top-down approach.     

The Heuristic Function of Mathematics in Physics and Astronomy

This paper considers the role of mathematics in the process of acquiring new knowledge in physics and astronomy. The defining of the notions of continuum and discreteness in mathematics and the natural sciences is examined. The basic forms of representing the heuristic function of mathematics at theoretical and empirical levels of knowledge are studied: deducing consequences from the axiomatic system of theory, the method of generating mathematical hypotheses, “pure” proofs for the existence of objects and processes, mathematical modelling, the formation of mathematics on the basis of internal mathematical principles and the mathematical theory of experiment.     

Arithmetization and Rigor as Beliefs in the Development of Mathematics

With the arrival of the nineteenth century, a process of change guided the treatment of three basic elements in the development of mathematics: rigour, the arithmetization and the clarification of the concept of function, categorised as the most important tool in the development of the mathematical analysis. In this paper we will show how several prominent mathematicians contributed greatly to the development of these basic elements that allowed the solid underpinning of mathematics and the consideration of mathematics as an axiomatic way of thinking in which anyone can deduce valid conclusions from certain types of premises. This nineteenth century stage shares, possibly with the Heroic Age of Ancient Greece, the most revolutionary period in all history of mathematics.     

The Surveyability of Long Proofs

The specific characteristics of mathematical argumentation all depend on the centrality that writing has in the practice of mathematics, but blindness to this fact is near universal. What follows concerns just one of those characteristics, justification by proof. There is a prevalent view that long proofs pose a problem for the thesis that mathematical knowledge is justified by proof. I argue that there is no such problem: in fact, virtually all the justifications of mathematical knowledge are ‘long proofs’, but because these real justifications are distributed in the written archive of mathematics, proofs remain surveyable, hence good.     

Mathematical Models and Reality: A Constructivist Perspective

To explore the relation between mathematical models and reality, four different domains of reality are distinguished: observer-independent reality (to which there is no direct access), personal reality, social reality and mathematical/formal reality. The concepts of personal and social reality are strongly inspired by constructivist ideas. Mathematical reality is social as well, but constructed as an autonomous system in order to make absolute agreement possible. The essential problem of mathematical modelling is that within mathematics there is agreement about ‘truth’, but the assignment of mathematics to informal reality is not itself formally analysable, and it is dependent on social and personal construction processes. On these levels, absolute agreement cannot be expected. Starting from this point of view, repercussion of mathematical on social and personal reality, the historical development of mathematical modelling, and the role, use and interpretation of mathematical models in scientific practice are discussed.     

Mathematical,Philosophical and Semantic Considerations on Infinity (I): General Concepts

In the Reality we know, we cannot say if something is infinite whether we are doing Physics, Biology, Sociology or Economics. This means we have to be careful using this concept. Infinite structures do not exist in the physical world as far as we know. So what do mathematicians mean when they assert the existence of ω (the mathematical symbol for the set of all integers)? There is no universally accepted philosophy of mathematics but the most common belief is that mathematics touches on another worldly absolute truth. Many mathematicians believe that mathematics involves a special perception of an idealized world of absolute truth. This comes in part from the recognition that our knowledge of the physical world is imperfect and falls short of what we can apprehend with mathematical thinking. The objective of this paper is to present an epistemological rather than an historical vision of the mathematical concept of infinity that examines the dialectic between the actual and potential infinity.     

数学中的经验:认识论上的紧张视角

就形式数学来说,它是脱离经验,在内涵上是一种社会建构。计算机技术提高了人们的计算能力,对数学的这一社会建构平添了紧张,加强了“作为计算的数学”与“作为证明的数学”之间的不平衡性。在历史上,相似的认识论上的争论表现在计算或实践的印度数学与精神或形式的西方数学之间。我们认为,认识论上的紧张,可通过以下方式得以消解:认同数学是基于经验、可错的观点,并据此引领数学课程标准的基本理念。     

20世纪上半叶中国高等数学教育的体制化

1913年北京大学数学门招生标志着中国现代高等数学教育的正式开始，从这时到20年代末是中国高等数学教育体制的初创期，这一时期归国留学生在国内高校创建了不少的数学系，高校中还出现了一些数学方面的团体和刊物，到20年代末中国高等数学教育体制初见端倪。1930－1937年是中国高等数学教育体制的形成期，这一时期全国数学系的规模不断扩大，随着归国留学生的日渐增多，高校师资力量也得到了加强，高校数学教学思想和教学方法也日渐成熟（这主要以清华大学、北京大学和浙江大学等的算学系或数学系为代表），许多高校在教学的同时还进行数学研究，并且还有几所高校开始培养数学专业硕士研究生，到1937年抗战爆发前夕中国高等数学教育体制已基本上形成。1937－1949年中国高等数学教育体制又得到了进一步的发展。     

中古算书中的田地面积算法与土地制度——以《五曹算经》"田曹"卷为中心的考察

关注了前人少有深入探究的一些中古实用算书的特点和相关社会制度背景.通过对有关社会经济史料和算书中的田地面积算题进行纵向和横向的比较与细密的分析,指出<五曹算经>中"田曹"的面积计算法具有求多而不求精的特点,与北朝田制特别是均田制下出现频繁测量、分划田地的急切需要有着密切的关系,<敦煌算书>、<夏侯阳算经>等书中田地面积计算法的特点,不仅与均田制的盛衰,而且与整个社会的文化和数学的发展有关,其中后者还带有编者讲求学理和精简的意图.社会因素不仅可以影响到数学讨论的对象,还可以影响到数学知识的本身.     

《缀术算经》:东亚数学归纳推理的典范

《缀术算经》是日本和算家建部贤弘最富创造性的一部和算著作,代表了当时日本数学发展的最高成就。文章在前人工作的基础上,从数学传播史和比较数学史的角度,将其置于整个汉字文化圈数学文化背景下,对其数学内容、思想实质与中国传统数学的关系予以深入分析,对其数学成就与建部贤弘的数学方法论予以客观公正的评价。     

数学发现和论证的两种原型:古希腊与古中国

萨博论点认为希腊数学证明源于埃利亚学派,但没有涉及与之相关的社会文化原因。把视野扩大到社会文化背景,可以发现,古希腊重甲步兵的出现以及其社会地位的提高,创造了以对抗或竞赛为象征的民族精神,从而既摆脱了怀疑主义哲学的束缚,又使得批判思维统治社会成为可能,这才是埃利亚学派及其数学产生的社会原因。另一方面,结合中国传统社会的考察,分析《九章算术》源于日常实践的问题以及复杂的理论回答,可以发现,中国古代需要大量人力完成的农业技术发展和日常生活中的实用技术发展,都得益于其算法的实用性,中国传统数学由此而成为东方数学的最高形式。两种数学实践的原型代表着两种重要的数学价值观,即确定性与实用性。     

Data Analysis: Models or Techniques?

In this commentary to Napoletani et al. (Found Sci 16:1–20, 2011), we argue that the approach the authors adopt suggests that neural nets are mathematical techniques rather than models of cognitive processing, that the general approach dates as far back as Ptolemy, and that applied mathematics is more than simply applying results from pure mathematics.     

Evolution of Mathematical Proof

The authors present the main ideas of the computer-assisted proof of Mischaikow and Mrozek that chaos is really present in the Lorenz equations. Methodological consequences of this proof are examined. It is shown that numerical calculations can constitute an essential part of mathematical proof not only in the discrete mathematics but also in the mathematics of continua.     

20世纪50年代中苏数学交流的特点及其对中国数学发展的影响

20世纪 5 0年代是苏联数学发展的强盛时期 ,也是中国全面开展向苏联学习的时期。从中国数学发展的角度看 ,中苏数学交流对于中国现代数学的发展产生了很大的促进作用 ,为建立中国自己的数学研究基础和体系打下了良好的基础。从中国和国际数学发展的背景出发 ,对一些原始档案材料和文献进行分析和研究 ,指出 2 0世纪 5 0年代中苏数学交流的方式、内容和结果。这一时期数学交流在中国表现的主要特点即学习苏联对数学研究进行整体规划 ,有计划地重点发展数学应用和应用数学 ,继续发展我国在国际数学界的强项专业以及重视数学史研究。并进一步探讨苏联数学在 2 0世纪 5 0年代对中国现代数学发展的影响。     

The Future of Mathematics in Economics: A Philosophically Grounded Proposal

The use of mathematics in economics has been widely discussed. The philosophical discussion on what mathematics is remains unsettled on why it can be applied to the study of the real world. We propose to get back to some philosophical conceptions that lead to a language-like role for the mathematical analysis of economic phenomena and present some problems of interest that can be better examined in this light. Category theory provides the appropriate tools for these analytical approach.     

无穷小量的命运及对数学发展动力的思考

近代力学的需要催生了无穷小量.历史上的数学家对无穷小量作了各种解读,试图论证它存在的合法性,以使微积分严密化,都没有成功.在19世纪末的数学公理化运动中,极限取代了无穷小量成为微积分的基础.无穷小量的曲折历史使人们认识到:数学有效性并不必须由其真理性来保证,数学家的信仰是数学发展的精神动力.近代数学家经历了从信仰上帝到信仰自然再到信仰数学内部的逻辑美的过程,数学家的任务也经历了从解决上帝、自然和数学三者之间的矛盾到解决自然和数学两者之间的矛盾,再到解决数学内部的矛盾过程.哥德尔不完备性定理抽走了数学家的逻辑美信仰,数学界出现了信仰危机.     

建部贤弘的数学认识论--论《大成算经》中的"三要"

“象形”、“满干”和“数”,是日本江户时代数学家建部贤弘在《大成算经》中所讨论的三个范畴 ,也是该书的纲纪 ,谓之“三要”。这些范畴来源于中国传统文化中的术数 ,语言晦涩 ,一直为日本数学史界所忽视。文章从中国数学文化传统出发 ,重新解读这些文字 ,提出一些全新的观点。认为在汉字文化圈数学家中 ,建部贤弘在中国象数学文化背景下 ,首次系统地阐述了数学科学的本质 ,讨论了数学研究对象及其存在性问题 ,并已接触到数学变量的讨论 ,同时对实数系给出了一种分类。其“三要”数理观是汉字文化圈数学认识论的突出反映 ,具有数学哲学意义。     

从“古为今用”到“丝路精神”:吴文俊数学史观的形成与演变

吴文俊的数学史观,来自他对中国数学史的独创性研究。在"古为今用"思想的引领下,开辟了数学机械化的新领域,让中国古代数学为世界数学作出新贡献;"古证复原"原则的确立,开启了中国数学史研究的新时代;"两种数学主流"思想的提出,确立了中国传统数学在世界数学发展史上的地位。更为重要的是,2002年,吴文俊指出"丝路精神"的核心价值是"知识交流与文化融合"。因此,"古为今用""古证复原""两种主流"和"丝路精神"构成了吴文俊数学史观的核心要素,是指引新时代中国数学史研究的伟大旗帜。