Actori incumbit onus probatio - "On the plaintiff rests the proving". The burden of proof falls to the plaintiff, claimant, or petitioner.⏎
Consensus facit legem - Stipulates that when two or more persons arrive at a good faith agreement, the law will insist on that agreement being carried out.⏎
Consuetudo pro lege servatur - "Custom is held as law". Where no laws apply to a given situation, the customs of the place and time will have the force of law.⏎