[ULPIANUS libro uicesimo quarto ad Sabinum. ] §35.1.12.prSi ita legatum sit: 'quoniam filius maior ex arca mea decem sustulit, heres minor filius decem e medio sumito', debetur legatum, quia idcirco relictum est, ut condicio filiorum exaequaretur.
[ULPIANUS in the twenty-fourth book on Sabinus.] If a legacy has been left in this manner: 'since the elder son has taken ten from my chest, let the younger son who is heir take ten from the common fund', the legacy is due, because it was left for the purpose of equalizing the condition of the sons.
et sane haec causa est: nam causa in praeteritum, poena in futurum confertur.
And indeed, this is a cause; for a cause is referred to the past, a penalty to the future.