We consider documents as the results of dynamic processes of documentary fragments’ associations. We have experi- enced that once a substantial number of associations exist, users need some synoptic views. One possible way of pro- viding such views relies in the organization of associations into relevant subsets that we call “dimensions”. Thus, di- mensions offer orders along which a documentary archive can be traversed. Many works have proposed efficient ways of presenting combinations of dimensions through graphical user interfaces. Moreover, there are studies on the struc- tural properties of dimensional hypertexts. However, the problem of the origins and evolution of dimensions has not yet received a similar attention. Thus, we propose a mech- anism based on a simple structural constraint for helping users in the construction of dimensions: if a cycle appears within a dimension while a user is creating a new dimension by the aggregation of existing ones, he will be encouraged (and assisted in his task) to restructure the dimensions in order to cut the cycle. This is a first step towards a rational control of the emergence and evolution of dimensions.