INTRODUCTION

The theme “from casus to regula” is particularly interesting in the law of persons. The sources of classical Roman law contain only case law (casus) about family matters and personal relations between house-mates and relatives. There were no rules (regulae). The way in which, at the end of the twelfth century, this case law was shaped into rules and systematic doctrine is significant for the history of medieval law.

THE ROMAN LAW OF PERSONS

In classical Latin a persona was a theatre mask, hence a character and a theatre player. In legal texts the word was used for the actors in a law suit. When the word occurs in the Corpus iuris civilis, it has thus to be understood as referring to one of the men present in court. It is accordingly found used for a plaintiff or pursuer, for a defender or defendant, and for the judge. An action in personam was not understood as an action against a person, but as an action against the defendant whose name was mentioned in its formula.

Gaius commenced his Institutes with the law of persons. In the first part of his book he described the situation of men in court. His reflections on slaves and family members are related to their representation in court. It is impossible to understand the first part of his Institutes without realising that the contents are about civil courts. Contemporary Romanists have to fight the tendency to find in Gaius rules of modern-time civil institutions. The example of tutela illustrates this well.