e not unaware of the offices which the copious and
malleable terminology belonging to this part of their system might be
made to discharge, and this is proved by their employment of the
peculiar adjunct _quasi_ in such expressions as Quasi-Contract and
Quasi-Delict. "Quasi," so used, is exclusively a term of
classification. It has been usual with English critics to identify the
Quasi-contracts with _implied_ contracts, but this is an error, for
implied contracts are true contracts, which quasi-contracts are not.
In implied contracts, acts and circumstances are the symbols of the
same ingredients which are symbolised, in express contracts, by words;
and whether a man employs one set of symbols or the other must be a
matter of indifference so far as concerns the theory of agreement. But
a Quasi-Contract is not a contract at all. The commonest sample of the
class is the relation subsisting between two persons one of whom has
paid money to the other through mistake. The law, consulting the
interests of morality, imposes an obligation on the receiver to
refund, but the very nature of the transaction indicates that it is
not a contract, inasmuch as the Convention, the most essential
ingredient of Contract, is wanting. This word "quasi," prefixed to a
term of Roman law, implies that the conception to which it serves as
an index is connected with the conception with which the comparison is
instituted by a strong superficial analogy or resemblance. It does not
denote that the two conceptions are the same or that they belong to
the same genus. On the contrary, it negatives the notion of an
identity between them; but it points out that they are sufficiently
similar for one to be classed as the sequel to the other, and that the
phraseology taken from one department of law may be transferred to the
other and employed without violent straining in the statement of rules
which would otherwise be imperfectly expressed.

It has been shrewdly remarked, that the confusion between Implied
Contracts, which are true contracts, and Quasi Contracts, which are
not contracts at all, has much in common with the famous error which
attributed political rights and duties to an Original Compact between
the governed and the governor. Long before this theory had clothed
itself in definite shape, the phraseology of Roman contract-law had
been largely drawn upon to describe that reciprocity of rights and
duties which men had always conceived as existing b