A principal hired a mortgage banking firm to obtain a loan commitment of $10,000,000 from an insurance company for the construction of a shopping center. The firm was promised a fee of $50,000 for obtaining the commitment. The firm was successful in arranging for the loan, and the insurance company, without the principal's knowledge, agreed to pay the firm a finder's fee. The principal then refused to pay the firm the promised $50,000, and the firm brought suit to recover the fee. May the firm recover the fee? Why?