Thomas Storer’s Heart Sequence: A Formal Approach to String Figure-Making
Résumé
String figure-making is a procedural activity carried out in many societies of oral tradition. It consists in producing geometrical forms using a string knotted into a loop. In 1988, an American mathematician, Thomas Storer (1938-2006), published a long article in which he developed several formal approaches of string figure-making. One of these is the Heart-sequence. Passing the string around a finger forms a "loop". The point is then to focus, during the process, on the movements of the loops without taking into account the way the fingers operate to make these loops, and to convert these movements into a mathematical formula. This mathematical approach to string figures allows a new reading of string figure procedures which makes it possible to classify them and is a promising way to carry out a comparative study of string figure corpora. This paper concentrates on
string figure algorithms leading to "double-sided lozenge" final figures. Although various different methods in forming such a "double-sided lozenge" can be found in geographically and culturally distant societies, only two classes of heart-sequences will be identified