[IDEM libro singulari de heurematicis. ] §28.6.4.prIam hoc iure utimur ex diui Marci et Ueri constitutione, ut, cum pater impuberi filio in alterum casum substituisset, in utrumque casum substituisse intellegatur, siue filius heres non exstiterit siue exstiterit et impubes decesserit.
[IDEM in the single book on Heurematica.] Now we enjoy this rule of law under a constitution of the Divine Marcus and Verus, namely, that when a father has substituted for his son under puberty for either of the two cases, he is understood to have substituted for both cases, whether the son does not become heir, or becomes heir and dies under puberty.
Quod ius ad tertium §28.6.4.1quoque genus substitutionis tractum esse uidetur: nam si pater duos filios impuberes heredes instituat eosque inuicem substituat, in utrumque casum reciprocam substitutionem factam uideri diuus Pius constituit.
This rule of law seems also to have been extended to a third class of substitution: for if a father institutes two sons under puberty as heirs and substitutes them for each other reciprocally, the Divine Pius constitutionally ordained that a reciprocal substitution is deemed to have been made for both cases.
§28.6.4.2Sed si alter pubes, alter impubes hoc communi uerbo 'eosque inuicem substituo' sibi fuerint substituti, in uulgarem tantummodo casum factam uideri substitutionem Seuerus et Antoninus constituit: incongruens enim uidebatur, ut in altero duplex esset substitutio, in altero sola uulgaris.
But if one is over puberty and the other under puberty, and they have been substituted for each other by this common expression, 'and I substitute them for each other,' Severus and Antoninus constitutionally ordained that the substitution is deemed to have been made only for the ordinary case: for it seemed incongruous that in the case of one there should be a double substitution, and in the case of the other only the ordinary one.
hoc itaque casu singulis separatim pater substituere debebit, ut, si pubes heres non exstiterit, impubes ei substituatur, si autem impubes heres exstiterit et intra pubertatem decesserit, pubes frater in portionem coheredis substituatur: quo casu in utrumque euentum substitutus uidebitur, ne, si uulgari modo impuberi quoque substituat, uoluntatis quaestionem relinquat, utrum de una uulgari tantummodo substitutione in utriusque persona sensisse intellegatur: ita enim in altero utraque substitutio intellegitur, si uoluntas parentis non refragetur.
Therefore, in this case, the father must substitute for each separately, so that, if the one over puberty does not become heir, the one under puberty is substituted for him; but if the one under puberty becomes heir and dies before reaching puberty, his brother over puberty is substituted for the share of the co-heir: in which case he will be deemed to have been substituted for either event, lest, if he substitutes for the child under puberty also in the ordinary way, he should leave a question of intention, whether he is to be understood to have intended only one ordinary substitution in the person of both; for in this way, both substitutions are understood in the case of one only if the intention of the parent is not opposed to it.
uel certe euitandae quaestionis gratia specialiter in utrumque casum impuberi substituat fratrem: 'siue heres non erit siue erit et intra pubertatis annos decesserit'.
Or at least, for the sake of avoiding any question, he should specifically substitute the brother for the child under puberty for both cases: 'whether he will not be heir, or will be heir and die within the years of puberty.'