ulation into a Verbal Contract.

The extreme importance of this history of Contract, as a safeguard
against almost innumerable delusions, must be my justification for
discussing it at so considerable a length. It gives a complete account
of the march of ideas from one great landmark of jurisprudence to
another. We begin with Nexum, in which a Contract and a Conveyance are
blended, and in which the formalities which accompany the agreement
are even more important than the agreement itself. From the Nexum we
pass to the Stipulation, which is a simplified form of the older
ceremonial. The Literal Contract comes next, and here all formalities
are waived, if proof of the agreement can be supplied from the rigid
observances of a Roman household. In the Real Contract a moral duty is
for the first time recognised, and persons who have joined or
acquiesced in the partial performance of an engagement are forbidden
to repudiate it on account of defects in form. Lastly, the Consensual
Contracts emerge, in which the mental attitude of the contractors is
solely regarded, and external circumstances have no title to notice
except as evidence of the inward undertaking. It is of course
uncertain how far this progress of Roman ideas from a gross to a
refined conception exemplifies the necessary progress of human thought
on the subject of Contract. The Contract-law of all other ancient
societies but the Roman is either too scanty to furnish information,
or else is entirely lost; and modern jurisprudence is so thoroughly
leavened with the Roman notions that it furnishes us with no contrasts
or parallels from which instruction can be gleaned. From the absence,
however, of everything violent, marvellous, or unintelligible in the
changes I have described, it may be reasonably believed that the
history of ancient Roman Contracts is, up to a certain point, typical
of the history of this class of legal conceptions in other ancient
societies. But it is only up to a certain point that the progress of
Roman law can be taken to represent the progress of other systems of
jurisprudence. The theory of Natural law is exclusively Roman. The
notion of the _vinculum juris_, so far as my knowledge extends, is
exclusively Roman. The many peculiarities of the mature Roman law of
Contract and Delict which are traceable to these two ideas, whether
singly or in combination, are therefore among the exclusive products
of one particular society. These later legal co