[IDEM libro singulari de ambiguitatibus. ] §28.6.31.prIn substitutione filio ita facta: 'quisquis mihi ex supra scriptis heres erit, idem filio heres esto', quaeritur, quisquis heres quandoque fuerit intellegatur an quisquis heres tum erit, cum filius moriatur.
[THE SAME, from the Single Book on Ambiguities.] In a substitution to a son made as follows: "Whoever of those written above shall be my heir, let the same be heir to my son," it is asked whether "whoever is heir" is to be understood as whoever has been heir at some time or other, or whoever shall be heir at the time when the son dies.
placuit prudentibus, si quandoque heres fuisset: quamuis enim uiuo pupillo heres esse desisset, forte ex causa de inofficioso, quae pro parte mota est, futurum tamen eum heredem ex substitutione creditum est.
The jurists held that it applies if he had been heir at some time or other; for although he had ceased to be heir during the lifetime of the ward, perhaps due to an action on an undutiful will which was brought in part, he was nevertheless believed to become heir under the substitution.
§28.6.31.1Non simili modo in hac specie dicendum est, si quis, cum filios duos haberet, Gaium puberem, Lucium impuberem, ita filio substituisset: 'si Lucius filius meus impubes decesserit neque mihi Gaius filius heres erit, tunc Seius heres esto': nam ita prudentes hoc interpretati sunt, ut ad impuberis mortem condicio substitutionis esset referenda.
We must not speak in a similar way in this case, if someone, having two sons, Gaius who was of age and Lucius who was under age, had substituted to his son as follows: "If my son Lucius should die under age and my son Gaius shall not be my heir, then let Seius be heir." For the jurists interpreted this in such a way that the condition of the substitution was to be referred to the death of the pupil.