[ULPIANUS libro septimo ad Sabinum. ] §28.5.19.prEx facto etiam agitatum Pomponius et Arrianus referunt, si quis uacua parte relicta ita instituerit: 'si mihi Seius heres non erit', quem non instituerat, 'Sempronius heres esto', an hic occupare possit uacantem portionem.
[ULPIANUS libro septimo ad Sabinum.] Pomponius and Arrianus report a debate arising from an actual case: if someone, having left a vacant share, has made an appointment in this way, 'If Seius will not be my heir,'—whom he had not appointed—'let Sempronius be my heir,' whether the latter can take possession of the vacant portion.
et Pegasus quidem existimat ad eam partem admitti: Aristo contra putat, quia huic pars esset data, quae nulla esset: quam sententiam et Iauolenus probat et Pomponius et Arrianus et hoc iure utimur.
And Pegasus indeed thinks that he is admitted to that share; Aristo, on the contrary, thinks not, because a share had been given to him which was non-existent. Javolenus also approves this opinion, as do Pomponius and Arrianus, and we follow this rule of law.