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.⏎
Dubia in meliorem partem interpretari debent - "Doubtful things should be interpreted in the best way". Often spoken as "to give the benefit of the doubt".⏎
Delegatus non potest delegare - That which has been delegated cannot delegate further.⏎