The conclusio pulchra, mirabilis et bona: an ingenious demonstration attributable to Nicole Oresme

Abstract

Hardly any other concept has occupied the minds of philosophers and scientists as much as the con-cept of infinity. Late medieval philosophy is not an exception. Especially within the context of the so-calledcalculatorestradition a new approach emerged which prioritised the analysis of physical, mathematical, and logical problems over the determination of the essence of infinity and its defini-tion. From the fourteenth century onward, it was not unusual in this context to discuss in detail some special cases of motion which included an augmentationin infinitumof the “degrees of velocity”. This paper focuses on a particular case, the “conclusio mirabilis”, a demonstration to which Oresme could have self-referred in this treatiseDe configurationibusas a “more subtle and more difficult” proof. Whereas this short text has until now been analysed according to only one manuscript, the present contribution involves a research regarding a text conglomerate made up of at least seven manuscripts which are somehow mutually connected. It is argued that an attribution of this demon-stration to Oresme is, with due caution, possible, even if further research is still needed to determine the original shape of the text. In addition, this paper includes a short reference to two later important authors, Biagio Pelacani da Parma and Jacques Almain, whose reception of theconclusio mirabi-lisremained unnoticed in the scholarship until now.