Let the purchaser take care; who ought not to be ignorant what right of another he purchases.
Certa debet esse intentio et narratio, et certum fundamentum, et certa res quæ deducitur in judicium.
The design and narration ought to be certain, and the foundation certain, and the matter certain, which is brought into court to be tried.
Certum est quod certum reddi potest.
What can be rendered certain is certain.
Cessa regnare si non vis judicare.
Cease to reign if there be no power to judge.
Cessante causa, cessat effectus.
The cause ceasing, the effect ceases.
Cessante ratione legis, cessat ipsa lex.