Cui Bono
A Dictionary of Law · Henry Campbell Black · 1891
A Dictionary of Law
For whose good; for whose use or benelit. “Czuéi bono is ever of great Mi 10 Mod. 135. Sometimes translated, for whiat good, for what useful purpose. Cuicunqwe aliquis quid concedit concedere videtur et id, sine quo res ipsa esse non potuit.
11 Coke, 52.
Whoever grants anything to another is supposed to grant that also without which the thing itself would be of no effect.