ABSTRACTS OF PAPERS
URANIUM IN THE CZECH HISTORY
(Uran v českých dějinách )
Mining and use of uranium ore in the Czech lands belongs to significant historical phenomena. The theme was taboo because of political reasons for tens of years from 1945, and only recently, when pertinent document were “declassificied”, opened to public, it could be properly studied. The author summarizes and evaluates accomplished results, giving simultaneously hints where the future research of the complicated topic could be focused.
In the introduction of the article there is characteristics of uranium ores in the Czech Massive and their mineralization, the development of mining and use of uranium for colour´s production from the beginnings of the 19th century, then from Marie Skłodowska-Curie’s discovery in 1902 to the factory extraction of radium, and reasons and amount of uranium production as military and strategic raw material that was forcedly expedited to the Soviet Union after 1945. Simultaneously there is an explanation given on mining technology and technology of production of radium and concentrate of uranium.
In special part the consequences and/or mutual correlation of uranium mining with social conditions and history are given, ie in many scientific branches in the 19th and 1st half of the 20th centuries, and on the contrary in the 2nd half of the 20th century its “misuse”, misapplication as a mean of repression against dissenters of the totalitarian establishment. Dissenters were kept in prison in 16 concentration camps in Jáchymov (Joachimsthal), Horní Slavkov, and Příbram. In the end of the article, there is an economical evaluation of the uranium mining between 1945–1990, reaching 98,481.1 tons.
JOSEF SEDLÁČEK—A NEGLECTED SCHOLAR OF BOLZANO´S LOGIC
(Josef Sedláček – opomenutý znalec Bolzanovy logiky )
B. Bolzano criticised in his Wissenschaftlehre (§120) the traditional rule that content and extent of concepts stand in an inverse relationship and exemplified his view by assuming that the idea “a man who understands all living European languages” has in respect to the idea “a man who understands all European languages” not only a greater content but a grater extent as well. The attempts to decide whether his argumentation is justified failed especially for two reasons. Bolzano held in opposition to the prevailing logical tradition that the components of compound contents are not notes, notae, i. e. ideas of properties, but simple concepts. An idea, or a concept, is not completely defined by its content, namely by the sum of its components. It is necessary to indicate as well how these parts are bound together. E. g. the ideas “a learned son of an unlearned father” and “an unlearned son of an learned father” have the same content, yet they are different.
This paper tries to show that a satisfactory explanation of Bolzano´s standpoint was presented by J. Sedláe`ek (1866–1923), a Moravian secondary teacher, in his Czech written textbook (1898). According to him the content of a concept is not merely the sum of its parts, i. e. its notes, but their connection as well. Hence such concepts as “history of philosophy” and “philosophy of history” are distinct concepts with different contents. Further, he connected the relationship of content and extent with the methods of abstraction and determinism and was convinced that these methods hold only in the case of one and the same hierarchically ordered sequence of concepts–the “systochia” (Aristoteles). According to his ingenious analysis which was nevertheless ignored, the controversial rule does not hold in three cases: 1) The determination or abstraction is not realised in an exactly same sequence of concepts. Bolzano´s example is, therefore burdened by an interference or contamination of two different sequences: of European languages and of their speakers or experts. 2) It does not hold for singular concepts. 3) It cannot be applied in the case of redundant concepts, e. g. “round sphere” in respect to “sphere", mentioned already by Bolzano. The first, most relevant exception was tacitly anticipated by A. Höfler (1890) in the formulation “Are there more people who understand all living European languages than people who understand all European languages". Obviously, the “systochia” of languages can be decided by a logical analysis, but the question concerning the number of speakers or experts can be solved only by empirical means.
A LA DATE DE LA NAISSANCE DE THADDAEUS HAGECIUS
(K datu narození Tadeáše Hájka )
Jusqu’a` présent, on ne connaissait pas la date exacte de la naissance de Thaddaeus Hagecius, astronome et médicin, le plus éminent savant de Bohe^me du XVIe`me sie`cle. Sans connaître le jour et le mois, on ne se servait que de l’an 1525 – d’une indication venant de la fin du XVIIIe`me sie`cle.
L’auteur cherche a` expliquer les raisons de l’absence des sources contemporaines et du fait que sa premie`re biographie n’apparaît qu’ a` la fin du XVIIIe`me sie`cle, presque deux cents ans apres sa mort.
Au cours de l’étude de la correspondance entre Hagecius et Tycho Brahe, l’auteur a découvert deux lettres (du 1 mai 1582 et du 13 décembre 1585) avec des données de me^me Hagecius concernat sa date de naissance. Cela lui a rendu possible préciser la naissance de Thaddaeus Hagecius au 1 octobre 1526.
© M. Barvík 2004