The libri singulares of Paul represent the most consistent group of works
ascribed to that jurist, and, at the same time, one of the most obscure literary product of the Roman juridical science: nevertheless, only a few scholars
have tried to take on the many problems raised by those books.
In this paper,
which is meant to be the first part of a more extended study, the author examines three of them (De articulis liberalis causae, De causae liberali and De libertatibus
dandis), which refer to the same subjects (causae liberales and manumissiones), in
order to get a better comprehension of this juridic material, and to give solution to some of the questions that still remain unanswered.