pable and yet established legal precepts which were not to
be denied held him answerable, it was because he was "deemed"
culpable, the historical legal liability being the proof of
culpability. If he had not actually assumed a duty, and yet
established legal precepts which were not to be denied held him to
answer for it, this must be because he had assumed some relation or
professed some calling in which an undertaking to that effect was
"implied" or had participated in some situation in which it was
"implied,"--the implication being a deduction from the liability. The
bases of liability were culpable conduct and legal transaction, and
these came down to an ultimate basis in will. The fundamental
conception in legal liability was the conception of an act--of a
manifestation of the will in the external world.

Roman law and English law begin with a set of what might be called
nominate delicts or nominate torts. In Roman law there were _furtum_
(conversion), _rapina_ (forcible conversion) and _iniuria_ (wilful
aggression upon personality). All these involved _dolus_, i.e.
intentional aggression. The _lex Aquilia_ added _damnum iniuria datum_
(wrongful injury to property). Later there were added what might be
called the equitable delicts of _dolus_ (fraud) and _metus_ (duress).
Here also there was wilful aggression, and the delict of _dolus_ gets
its name from the intentional misleading that characterizes it in
Roman law as it does deceit in English law. In _damnum iniuria datum_,
a wider conception of fault, as distinguished from intentional
aggression, grew up by juristic development, and Aquilian _culpa_,
that is, a fault causing injury to property and therefore actionable
on the analogy of the _lex Aquilia_, furnished the model for the
modern law. All these may be fitted to the will theory and modern
systematic writers regularly do so. But noxal liability for injury
done by a child or slave or domestic animal did not fit it, nor did
the liability of a master of a ship, an innkeeper or a stable keeper
to respond without regard to fault. Liability for injury done by child
or slave or domestic animal was enforced in a noxal action on the
analogy of the action which lay for the same injury if done by the
defendant in person. Hence procedurally it seemed liability for a
delict involving intentional aggression, and it was possible to say
that there was fault in not restraining the agency that did the
injury, although no fau