[PAULUS libro singulari de conceptione formularum. ] §44.1.20.prExceptiones opponuntur aut quia factum sit quod fieri oportet, aut quia factum sit quod fieri non oportuit, aut quia factum non sit quod fieri debuerat.
[PAULUS in his single book on the Drafting of Formulas.] Exceptions are opposed either because that has been done which ought to be done, or because that has been done which ought not to be done, or because that has not been done which ought to have been done.
quia factum est, quod fieri oportuit, datur exceptio rei uenditae et traditae et rei iudicatae: quia factum est, quod fieri non oportuit, datur exceptio doli mali: quia non factum est, quod fieri debuit, ut bonorum possessionis non datae.
Because that has been done which ought to be done, the exception of a sold and delivered thing and the exception of a res judicata are granted; because that has been done which ought not to be done, the exception of dolo malo is granted; because that has not been done which ought to have been done, for example, the exception of an ungranted possession of goods.