Several types of evidence may justify preference:
1. Chains and transmitters: accuracy, continuity, independent corroborating routes, and special familiarity with a teacher.
2. Transmission method: direct hearing or other reliably established modes of reception.
3. Wording and implication: preserved exact wording, clarity of the legal indication, and the correct general or specific scope.
4. External support: correspondence with other established evidence or well-grounded circumstances.
No single maxim is an infallible mechanical rule. For example, a larger number of routes provides little advantage if they all depend on one identifiable error.