The Informal Logic of Mathematical Proof

Informal logic is a method of argument analysis which is complementary to that of formal logic, providing for the pragmatic treatment of features of argumentation which cannot be reduced to logical form. The central claim of this paper is that a more nuanced understanding of mathematical proof and discovery may be achieved by paying attention to the aspects of mathematical argumentation which can be captured by informal, rather than formal, logic. Two accounts of argumentation are considered: the pioneering work of Stephen Toulmin [The uses of argument, Cambridge University Press, 1958] and the more recent studies of Douglas Walton, [e.g. The new dialectic: Conversational contexts of argument, University of Toronto Press, 1998]. The focus of both of these approaches has largely been restricted to natural language argumentation. However, Walton's method in particular provides a fruitful analysis of mathematical proof. He offers a contextual account of argumentational strategies, distinguishing a variety of different types of dialogue in which arguments may occur. This analysis represents many different fallacious or otherwise illicit arguments as the deployment of strategies which are sometimes admissible in contexts in which they are inadmissible. I argue that mathematical proofs are deployed in a greater variety of types of dialogue than has commonly been assumed. I proceed to show that many of the important philosophical and pedagogical problems of mathematical proof arise from a failure to make explicit the type of dialogue in which the proof is introduced.Comment: 14 pages, 1 figure, 3 tables. Forthcoming in Perspectives on Mathematical Practices: Proceedings of the Brussels PMP2002 Conference (Logic, Epistemology and the Unity of the Sciences Series), J. P. Van Bendegem & B. Van Kerkhove, edd. (Dordrecht: Kluwer, 2004

Programmation par objets avec Ada 9X

Ada 9X, la d finition r vis e du langage de programmation Ada, int gre la programmation par objets. Cet article examine les nouvelles caract ristiques du langage propres la programmation par objets, leur utilisation et leur int gration avec le typage fort de Ada. Nous couvrons les m canismes fondamentaux li s aux objets, tels que l'h ritage et le polymorphisme. Nous montrons ensuite comment combiner ces m canismes en de pr cieuses pratiques de programmation, comme la programmation par extension, les structures de donn es h t rog nes, et l'h ritage par mixin. Ada 9X, the revised definition of the Ada programming language, supports object-oriented programming. This paper examines the new, object-oriented features of the language, their use, and how they fit into Ada's strong type system. Basic object-oriented mechanisms are covered, such as inheritance and polymorphism. We then show how to combine these mechanisms into valuable programming techniques; topics include programming by extension, heterogeneous data structures, and mixin inheritance

Ada: Young, Smart and Evolving

The Ada language is now 10 years old, like SI and SI-Information. A free compiler, called GNAT, will soon be available from the Free Software Foundation (GNU). Ada is heavily used in high-tech applications. After 10 years, it was felt Ada should be revised. This revision is well on its way, and we describe here the structure of the revised language definition, as well as an overview of the object-oriented features of the language

Reading habits of rural and urban children

Misel Toneta Pavčka »Če ne bomo brali, nas bo pobralo.« je bila uporabljena že ničkolikokrat, a še vedno zadane bistvo. Branje ni pomembno le na ravni posameznika, z branjem besedil v slovenskem jeziku se ohranja slovenska kultura, slovenski jezik. Na ravni posameznika pa branje lahko predstavlja oddih, pobeg v navidezno resničnost, kjer je oseba sama s knjigo, razmišlja o njej in z njo. Branje pri otrocih spodbuja mišljenje, razvija njihove kognitivne sposobnosti in jim ne nazadnje omogoča prehod v svet odraslih. Vsi ljudje, odrasli in otroci, imamo v »moderni dobi« na voljo nešteto drugih vizualno privlačnejših reči za krajšanje prostega časa. To bi lahko pomenilo, da za branje preprosto ni časa, ampak temu ni oziroma ne bi smelo biti tako. Starši bi morali pri otrocih znati razporediti čas za igro, krožke, tehnološke naprave in čas za branje, predvsem pa bi morali že v ranem otroštvu otrokom brati in jih s tem spodbujati k branju. Magistrska naloga ima dva dela. V prvem, teoretičnem delu, je opisano branje, družinsko branje, branje v šoli, branje kot družbeno-kulturni proces, motivacija za branje, opisani so tudi dejavniki, ki vplivajo na bralne navade. V empiričnem delu so prikazani rezultati pridobljeni s pomočjo anketnega vprašalnika o bralnih navadah podeželskih in mestnih otrok. Rezultati anketnih vprašalnikov so bili obdelani v SPSS-programu za statistično analizo. Raziskava temelji na odgovorih 51 učencev iz osnovnih šol v Zgornji Savinjski dolini in 55 učencev iz osnovne šole v Ljubljani. Ugotovili smo, da podeželski otroci berejo več, da knjige, ki jih berejo pri pouku književnosti in za domače branje, ocenjujejo kot bolj zanimive. Analiza je pokazala, da med podeželskimi in mestnimi otroki ni razlik v mnenju o težavnosti knjig, ki jih obravnavajo v šoli, so pa razlike v mnenju o prilagajanju nalog in besedila s strani učitelja, večjemu deležu podeželskih otrok se zdi, da jim učitelj prilagodi naloge glede na zmožnosti. Večina otrok najraje bere knjige, ki si jih sami izberejo. Spoznali smo, da doma s starši bere in se po branju o prebranem pogovarja večji delež podeželskih otrok.Tone Pavček’s thought “[i]f we don\u27t read, we will disappear” has been used many times before but still hits the mark. Reading is not important only at individual levelby reading texts in Slovene we also keep Slovenian culture and language alive. For an individual, however, reading can present a short break, an escape to virtual reality, where a person is alone with a book, thinks about and with it. Reading at young age stimulates thinking, develops children’s cognitive abilities, and, lastly, helps them with transition to the adulthood. Available to all people, adults and children, in the “modern era” are many visually more attractive things than reading to keep us busy in our free time. This could mean there is simply no time for reading, but that is not the case or at least it should not be. Parents should know how to distribute the playtime, time spent on technological devices and reading, and first and foremost they should read to children already early on in their childhood and with that encourage them to read themselves. The Master’s Thesis has two parts. In the first, theoretical part, reading, family reading, reading in school, reading as a socio-cultural process, motivation for reading, and factors which have impact on reading habits are described. In the empirical part the results gathered with the help of survey questionnaire about reading habits are presented. The obtained results were processed in SPSS software for statistical analysis. The research is based on answers from 51 pupils of primary schools in the Upper Savinja Valley and 55 pupils of a primary school in Ljubljana. We came to the conclusion that rural children read morethey evaluate books they read in their literature class and for their family reading as more interesting. The analysis has shown no differences between rural and urban children when it comes to their opinion on difficulty of the books they read in school. There are, however, differences between pupils’ opinions of the teacher’s adjustment of the tasks and textsa higher percentage of rural children think their teacher adjusts the texts and tasks according to their capabilities. The majority of children prefer to read books they choose. We have noted that a larger part of rural children in comparison to urban children reads at home alongside their parents and also a bigger part of rural children talks with their parents about what they have read

Advanced Object-Oriented Programming with Ada 95

Ada 95 -the revised definition of the Ada programming language- provides support for object-oriented programming. This course offers a comprehensive view of object-oriented programming with Ada; it is divided in four parts. First, we examine the object-oriented features of the language, their use, and how they fit into Ada's strong type system and genericity mechanisms. Basic object-oriented mechanisms are covered: extension, inheritance, and polymorphism. Second, we show how to integrate these mechanisms into good programming practices; topics include incremental programming, heterogeneous data structures, mixin and sibling inheritance. We then demonstrate the proper use of these features in order to design for reuse, and to transition smoothly from Ada 83 to Ada 95. Finally, we compare standard object-oriented idioms in Ada vs. major object-oriented languages (e.g. C++, Smalltalk, Eiffel)

Ada 9X for Object-Oriented Programming

Ada 9X -the revised definition of the Ada programming language- provides support for object-oriented programming. This course examines the new, object-oriented features of the language, their use, and how they fit into Ada's strong type system and genericity mechanisms. Basic object-oriented mechanisms are covered, such as: extension, inheritance, and polymorphism. We then show how to integrate these mechanisms into good programming practices; topics will include incremental programming, heterogeneous data structures, mixin inheritance, and design for reuse. We will also compare standard object-oriented idioms as implemented in Ada vs. other object-oriented languages (e.g. C++, Eiffel)

The Loseley manuscripts. Manuscripts and other rare documents, illustrative of some of the more minute particulars of English history, biography, and manners, from the reign of Henry VIII. to that of James I., preserved in the muniment room of James More Molyneux, esq. at Loseley house, in Surrey ...

Mode of access: Internet

How to draw a straight line ; a lecture on linkages.

"One of the series delivered to science teachers last summer [1876] in connection with the loan collection of scientific apparatus."Mode of access: Internet