It is a coherent body of same type of text and it reveals the transmission of the same intellectual practice (with continuities and discontinuities) among European universities. Investigated as a whole, this corpus will show to what extent the principia offer a wealth of material for various investigations excavating the unknown connection among ignored authors. The corpus of the project is based on a present census of extant manuscripts, which does not take into consideration the already edited versions; there are, however, numerous anonymous principia, which will considerably enrich the corpus. A complete census will be available online by the end of the project and will offer a major point of orientation for further scholarly work in the field of medieval universities.