Consent as Basis of Contract
While the Romans did not regard consent as the legal basis of a contract (except in the case of the Consensual Contracts), they in later times fully recognized the principle that contracts are in fact the result of consent (Dig. 44, 7, 3, 1).
And in a legal sense two or more persons are said to consent when they agree upon the same thing in the same sense (Dig. 2, 14, 1, 2).