Bonae fidei possessor fructus consumptos suos facit. Tentative answers to some questions left open by Petrazycki's Economic Analysis of law

L. Petrażycki towards the end of 19th century was dealing with economic aspects of Roman law, namely the apportionment of fructus between its owner and its possessor. Petrażycki’s discussion of an apparent paradox in Roman law is then presented and commented. The analysis focuses on the question of relationship between the socio-economic functions of rules selected by case law and the cause of the fact that the rules have been selected. In the end two hypotheses are formulated, based on Patrażycki and Priest (1977): one that rule is selected that allows for more control or extension and second, that rules more balanced in regards to both parties. interests are selected. Author claims the hypotheses are falsifiable.