The law with regard to principal and agent grew up as part and parcel of the law of contracts. The law with regard to master and servant grew up as part and parcel of the law of torts. Each one takes its origin far back in the history of the common law.
Agents were used in an early day to effect livery of seisin, to create covenants, and to carry on commercial transactions. The terms "principal" and "agent" may be of modern origin. But the power of one person to bind another in legal transactions was familiar in the days of the Year Books."The agent was able, by his act of consent, to transfer his principal's property, to obligate his principal, and otherwise to bind him in legal transactions.' In order that an agent's acts should be effective, it was necessary that the agent should have authority.
Bases for Master's Liability and for Principal's Liability to Third Persons,
4 Vanderbilt Law Review
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