De transactionibus axiomata

LXXIIII.
But if the defendant has been induced to settle by the fraud of the plaintiff, we think it should be said according to the opinion of Petrus and Cynus that the settlement is valid by the law itself; nevertheless, an exception of bad faith will oppose the plaintiff acting from the settlement, and if anything has been paid by reason of the settlement, it will be recovered as an undue payment.

LXXV.
Clearly, if the calumny of either is evident, the settlement is null by the law itself, whether it was extorted by the fraud of the defendant or the plaintiff.

LXXVI.
However, what was said about a settlement being rescinded on account of fraud should be understood as follows: if he who suffered the fraud petitions this, not he who induced the other to settle by fraud. For the laws help those who have been deceived, not those who deceive.

LXXVII.
Likewise, if the fraud of either of the settlers is argued, not that of an outsider: in which case the settlement remains in its own right, and an action of fraud is given to the deceived against the outsider.

LXXVIII.
But also if it is proven that it was specifically settled concerning the fraud that was admitted in settling, the settlement will be fixed.

LXXIX.
But whether a settlement is rescinded on account of a lesion beyond half of the just price, the opinions of the Doctors are dissenting. We think it truer that it is not rescinded for that reason, provided it is perfect and absolute in its parts, which it has been observed the Imperial Chamber has also followed several times.