Final answer:
The phrase 'the law of agency is common-law doctrine' refers to the concept that the rules governing the relationship between agents and principals, as well as third parties, are derived from court decisions and not written statutes. This is part of the broader common law system, where legal principles are developed through judicial decisions and the doctrine of precedent.
Step-by-step explanation:
The phrase 'the law of agency is common-law doctrine' means that the regulation of the relationships between agents and principals, as well as agents and third parties, has been established by precedents set by court decisions rather than by statutory law. Common law comprises the body of law developed by judges, courts, and similar tribunals, which is known for relying heavily on precedent, meaning that decisions made in previous cases are taken into account when making rulings in new cases. This is different from a code law system where laws are detailed and leave little room for judicial interpretation.
One of the foundations of common law is its ability to adapt and apply principles to new situations while maintaining consistency with past judicial decisions. This allows for individual interpretation and application of the law in the judicial process. The law of agency is an excellent example of how common law evolves over time, with judges interpreting and refining legal principles as they apply them to specific cases.