[§ 10. Of Quasi-Contract.]

Quasi-contract is founded on the duty of restitution. If you find a watch on the way, you are obliged to restore it by the right of property, because a man loses not property with possession. But if you and I balance accounts, and you pay me a sum which both think due, but you afterwards find you did not owe that sum, how Edition: current; Page: [135] will you claim it? You cannot ask it as your property, for you alienated that sum, nor can you claim it by contract, for there never was one made between us1, yet it is evident that I am a gainer by your loss, and therefore restitution is due.

In the same manner if a man was called away by a sudden order of the state without leaving an attorney to manage a law suit that he had going on, and a friend undertakes this office without commission, as the defence is necessary, and the undertaking it prudent, restitution of his expenses are due. On the same principle were founded the actiones contrariae of the Roman law. If you lent me a horse which had cost me extraordinary expenses, by the contract commodate you could redemand your horse in the same [state] in which you lent him, but I could claim my extraordinary expenses by an actio contraria. The same principle takes place in many other cases. If a person borrows money, and gets three of his acquaintances sureties for him, jointly and severally, and if he turn bankrupt, the creditor pursues the ablest surety, who has a claim by the duty of restitution on the other two for their thirds. The Scotch law carries this still farther. If a bankrupt had two estates, and two creditors A and B: A has a security on both estates, B has security only on the best: A has a liberty of drawing his money from either estate he pleases, and draws from that on which B has his security. As B in this case is cut out, the law obliges A to give up his security on the other estate to B. The same was the case in the Roman law with regard to tutory.