Vladimir Pletser1 And Dirk Huylebrouck2
1European Space Agency, P.O. BOX 299, NL-2200 Noordwijk, The Netherlands
2Sint-Lucas Institute of Architecture, Paleizenstraat 65-67, 1030 Brussels, Belgium
(Received November 19, 1999: Accepted December 22, 1999)
Keywords: Archaeology, Mathematics, Art
Abstract. In 1950, the Belgian Prof. J. de Heinzelin discovered a bone at Ishango, a Congolese village at the sources of the Nile. The artefact has patterned notches, making it the first tool showing logic reasoning. Here, Pletser proposes his new "slide rule" interpretation, rejecting former "arithmetic game" and "calendar" explanations. Counting methods of present day civilisations in Africa provide circumstantial evidence for Pletser's hypothesis. Moreover, it confirms de Heinzelin's archaeological evidence about relationships between Egypt, West Africa and Ishango. It points towards the use of the base 12, which anthropologist Thomas had studied in West Africa some 80 years ago. It appears that the Ishango artefact is the missing link Thomas was looking for. These results where obtained independently; for instance, space scientist Pletser just stumbled over the Ishango artefact as he favoured the project of carrying it into space, as an African equivalent of the Katachi-symmetry relationship.