ABSTRACT
Earlier on, when Nkosi managed to fi x, temporarily, the bottle into a hole in the timber, he formed a near right-angular attachment or join. I mentioned that rightangular structure, along with the closed-shape are important Third Generation Structures in human childhood development and that we can also see these structures emerging in chimpanzee investigation and play. When Nkosi fi xes the plastic bottle into a hole at right-angles to a beam he is essentially making a Euclidean geometrical relationship. The bottle does not merely touch the beam, as in a topological relationship, it is joined (albeit for a moment only). Moreover, its fi xture into the hole by its bottle neck necessitates this rigid, perpendicular connection with the vertical post. What other kinds of angular shapes possessing measurable, Euclidean properties can the chimpanzees make?
