Note 469 — Chapter XXI · THE LAW OF OBLIGATIONS.
Reading edition
Commentaries III. 160. “A cause of action of contract arises not merely where one party has broken a legally binding agreement with the other, but where two parties stand in such a mutual relation that a sum of money is legally due from the one to the other, in which case the law is said to imply a contract to pay the money.” Clerk and Lindsell, Law of Torts, p. 1.