[AFRICANUS libro nono quaestionum. ] §39.1.15.prSi prius, quam aedificatum esset, ageretur ius uicino non esse aedes altius tollere nec res ab eo defenderetur, partes iudicis non alias futuras fuisse ait, quam ut eum, cum quo ageretur, cauere iuberet non prius se aedificaturum, quam ultro egisset ius sibi esse altius tollere.
[AFRICANUS, Questions, book nine.] He says that if, before a building was erected, an action was brought declaring that the neighbor had no right to raise his building higher, and the matter was not defended by him, the role of the judge would have been no other than to order the person against whom the action was brought to give security that he would not build until he had himself brought an action and proved that he had the right to raise it higher.
idemque e contrario, si, cum quis agere uellet ius sibi esse inuito aduersario altius tollere, eo non defendente similiter, inquit, officio iudicis continebitur, ut cauere aduersarium iuberet nec opus nouum se nuntiaturum nec aedificanti uim facturum.
And conversely, he says, if someone wished to bring an action declaring that he had the right to raise his building higher against the will of his adversary, and the latter likewise did not defend, it will be within the duty of the judge to order the adversary to give security that he will neither give notice of a new work nor use force against the builder.
eaque ratione hactenus is, qui rem non defenderet, punietur, ut de iure suo probare necesse haberet: id enim esse petitoris partes sustinere.
And in this way, the one who does not defend the matter is penalized to this extent, that he is obliged to prove his own right; for this is to sustain the role of the plaintiff.