Reflections on the origin and scope of so-called laesio enormis: This paper attempts to show that the doctrine of so-called laesio enormis has its roots neither in social or economic reasons nor in moral or religious reasons. In the famous constitution C. 4,44,2 (lex secunda) Gregorius, a secretary of petitions under emperor Diocletian, has to solve a delicate juridical problem concerning agency: A father had sold land belonging to his son (as a procurator) for less than half of its true value, obviously committing fraud. According to classical law (Iul. D. 41,4,7,6) the dominus negotii is allowed to sue a buyer of good faith if his procurator sells land below value for the sole purpose of causing loss. But as a son is not allowed to assert his father’s dolus (cf. for example C. 2,50,5,1), C.4,44,2 establishes objective criteria instead in order to decide in favour of the son. This allows us to explain the ultra dimidium rule, the criterion of pretium iustum, the right of the buyer to pay the difference, as well as the facts that the lex secunda is cited in C. 4,44,8 (by Hermogenian) as a precedent and that later constitutions (as CTh. 3,1,1; 4; 7) ignore a laesio ultra dimidium. Futhermore the paper discusses the procedural rules of the rescission of such a sale under Diocletian.
© 2021 Walter de Gruyter GmbH, Berlin/Boston