[IDEM libro decimo quaestionum. ] §18.7.7.prSeruus ea lege ueniit, ne in Italia esset: quod si aliter factum esset, conuenit citra stipulationem, ut poenam praestaret emptor.
[THE SAME in the tenth book of Questions.] A slave was sold under the condition that he should not be in Italy; and it was agreed, without a stipulation, that if it should be otherwise, the buyer should pay a penalty.
uix est, ut eo nomine uindictae ratione uenditor agere possit, acturus utiliter, si non seruata lege in poenam quam alii promisit inciderit.
It is hardly possible that the seller can bring an action on that account by reason of vengeance, but he will bring an action effectively if, because the condition was not observed, he has incurred a penalty which he promised to another.
huic consequens erit, ut hactenus agere possit, quatenus alii praestare cogitur: quidquid enim excedit, poena, non rei persecutio est.
It will follow from this that he can only bring an action to the extent that he is compelled to pay to the other; for whatever exceeds this is a penalty, not the pursuit of his interest.
quod si, ne poenae causa exportaretur, conuenit, etiam affectionis ratione recte agetur.
But if it was agreed that he should not be exported for the purpose of punishment, the action will also be rightly brought by reason of affection.
nec uidentur haec inter se contraria esse, cum beneficio adfici hominem intersit hominis: enimuero poenae non inrogatae indignatio solam duritiam continet.
Nor do these rules seem to be contrary to each other, since it is of interest to a human being that a human being should be treated with kindness; indeed, indignation that a punishment was not imposed contains only cruelty.