To the modern analyst of the law debt does not seem a real contract; since the obligation of the debtor is not to repay specific money but merely a certain amount of money. In the early law, however, the conception of a debt was analogous to that still popular in regard to money deposited in a bank. The depositor conceives himself the owner of a specified sum of the bank's money rather than a mere creditor of the bank for money lent.32 A debt might exist not only for the payment of money but also for chattels;33 and the judgment which the plaintiff recovered in either case was for the amount of money or of chattels due him, and damages for its detention. Debt would not he for the recovery of an unliquidated demand.34 This rule shows the conception at the foundation of the action, that the plaintiff was seeking to recover specific property. A debt might arise (1) upon a judgment or (2) upon a formal contract for the payment of a fixed sum of money,35 or (3) upon a quid pro quo which the debtor had received.
30In this respect the action of as-sumpsit was not carried so far in regard to goods as in regard to money. A plaintiff was allowed to recover in indtbiiatus assumpsit money which equitably belonged to him against a defendant who had tortiously received it, but no fictitious implied promise Kerns to have been invented from the wrongful possessor of goods in favor of the person justly entitled to them. At least actions based on this theory were not brought, though indebitatus assumpsit would lie for chattels. Falmouth v. Penrose, 6 B. ft C. 385; Mayor of Reading p. Clarke, 4 B. & Ald 268.
31 lChitty on Pleading (6th Eng. ed.), 121.
32 This theory of the early lawyers has often been remarked upon. Lang-dell, Summary of Contracts, Sec. 100; Ames, 8 Harv. L. Rev. 260.
33 8 Harv. L. Rev. 260, n. I. "Detinue was the proper remedy for the recovery of a specific chattel; debt, on the other hand, for the recovery of a specific amount of unascertained chattels."
34Y. B. 12 Edw. TV, 9 pi. 22; Young v. Ashburnham, 3 Leon. 161; Mason v. Welland, Skin. 238, 242.
35 Debt was the exclusive remedy in such a case until the seventeenth cen-
The quid pro quo might be anything which could be regarded as beneficial to the debtor. In early times it was usually a sale, a loan, a lease, or work. Later, less tangible benefits were held sufficient, as a release or forbearance, but mutual promises were insufficient to create mutual debts. Originally it was also necessary that the quid pro quo should be given to the debtor himself. To give it to a third person even at the debtor's request was insufficient; but this rule, subsequently, gave way, and anything which might be a quid pro quo if furnished to the defendant himself would also create a debt if furnished to a third person at the request of the defendant; provided, however, that the person to whom the benefit was given, himself was under no obligation to pay for it; for it remained permanently a requirement that one quid pro quo could not create two debts. If the person receiving the quid pro quo, therefore, was indebted on account of it, no other person could be. Accordingly a guarantor is not a debtor even though goods were sold to the principal debtor, or work done for him at the guarantor's request.36