Mathematicians of Vrije Universiteit Brussel design unique maths costume for Manneken Pis

“Manneken Pisthagoras” is a tribute to both maths and Brussels

Mathematics is the basis of the sciences and pioneering technologies such as AI. Yet there is too little interest in the field of study. In order to change this, the Department of Mathematics at the Vrije Universiteit Brussel has created the very first mathematics suit for Manneken Pis. Belgium’s best-known icon can wear the costume on the occasion of a day celebrating maths, such as Pi Day on 14 March.

For the design of the outfit, the initiators drew inspiration from the Greek mathematician Pythagoras, known as the father of geometry, whose theorem is part of the curriculum. The costume consists of a white and purple gown. The choice of purple as the accent colour next to white, which is typical for antiquity, is not coincidental: it is the colour of the Faculty of Sciences at VUB. For the headgear, a turban was chosen, referring to the journeys Pythagoras regularly made to Babylon. The turban rests on a “klak”, a typical student cap, which is often decorated with buttons and slogans. The one worn by Manneken Pis will reference Brussels and mathematics.

As a final part of the outfit, the VUB mathematicians and Nicolas De Coster of FabLab ULB have developed an accessory that illustrates Pythagoras’ theorem: a plane with a triangle on it. Each side of that triangle is bordered by a square, with the squares on the two short sides filled with water. The construction regularly rotates 180° so that the water from the two squares overflows and fills the third, and largest, square completely.

Dr Ann Kiefer, who is responsible for the initiative with fellow postdoctoral researcher Dr Leo Margolis, explains: “Manneken Pis has more than 1,000 costumes that refer to the most diverse themes. But not a single costume about mathematics, which occupies an important place in our daily lives. And it’s also just an exciting field that is still full of surprises, even for mathematicians themselves. With ‘Manneken Pisthagoras’, we hope to put mathematics on the map at home and abroad. The design has meanwhile been officially approved by the City of Brussels, so now our seamstress Julie De Kezel can really get started.”