Dimitar STOYANOV 15
LESIJ NO. XXIII, VOL. 1/2016
distinguish between enforceable promises
and accidental agreements when additional
requirements were considered to be an
exception rather than a rule. The need to
establish new abstract criteria to be used as an
essential element of the validity of contracts
and as indicia of seriousness brought the
modern theory of causa to life.
However, Roman law did not play a
significant part in moulding modern private
law everywhere in Europe. This is the reason
why English common law did not adopt the
concept of causa, but rather developed its own
methods to determine which promises could
be enforceable and the ultimate result of this
process, lasting for centuries, became known
as the doctrine of consideration.
The similarity of the two concepts is
beyond doubt. They share some common
features, yet there is a considerable difference
in terms o f notion, scope of application and
legal consequences between them, which
prevents the statement that the former is a
complete functional equivalent of the latter.
Moreover, there is a third group of
national legislations where neither causa nor
consideration is acknowledged as a vital
element of the contracts. It is sufficient for an
agreement to be both valid and enforceable
when there is mutual consent of the parties
upon its primary points.
The main aim of this article is to analyse
these three types of legal approach to the
question how to distinguish between a simple
agreement and a valid contract by presenting
the theory of causa and the doctrine of
Zimmermann, R., The Law of Obligations. Roman Foundations of the Civilian Tradition, (Cape Town, Wetton,
Johannesburg: Juta & Co, Ltd, 1992), 549.
Lorenzen, E., “Causa and Consideration in the Law of Contracts”, Yale Law Journal 7 (1919): 630.
Peterson, S., “The Evolution of “Causa” in the Contractual Obligations of the Civil Law” Bulletin of the
University of Texas, 46 (1905): 39.
Daruwala, P., The Doctrine of Consideration Treated Historica lly and Comparatively, (Calcutta: Butterworth
& Co., 1914), 367.
Buckland, W., Roman Law and Common Law. A Comparison in Outline, (Cambridge University Press, 1965), 227.
See Zimmermann, R., The Law of Obligations, op.cit., p. 551.
consideration in a comparative perspective,
trace its origin, present and future tendencies.
2. Origin of the causa
As far as the origin of causa is
concerned, many authors state is that it is a
totally un-Roman concept
, that no general
theory of causa could be deduced from the
and even that having such an
abstract principle was impossible for the
Romans because of the primitivism of their
legal system that excluded any possibility of
dealing with abstractions
. Although the
presence of causa as a concept in Roman
private law is admitted by a few scholars, they
point out that it was used in various senses,
differing immensely from the modern notion
. The vast majority of the authors
agree upon the fact that the earliest ideas of
causa emerged as the result of the canonists’
interpretations; a sophisticated medieval
attempt to generalise various figures
belonging to Roman private law
. St. Thomas
Aquinas developed the idea that every effect
is dependent upon its reason (causa) and
causa is something without which a thing
cannot exist. If everything is based on a causa,
he said, this should apply to contracts as well.
Influenced by St. Thomas Acquinas, the
glossator Baldus, while interpreting the
Roman contract of stipulation, stated that all
contracts have a causa – the “nominate” carry
it within themselves, while the abstract (such
as the stipulation) receive it from outside
Other scholars assume that the origin of causa
can be found several centuries later, when the