ere in the world. But for a season our
category of mercantile specialties had ceased to admit of growth and
the doctrine of consideration with its uncertain lines stood in the
way of many things which the exigencies of business called for and
business men found themselves doing in reliance on each other's
business honor and the banker's jealousy of his business credit, with
or without assistance from the law. Certainly no one would say that
such a situation bears witness to wise social engineering in an
economically organized society resting on credit.

Two circumstances operate to keep the requirement of consideration
alive in our law of simple contract. One is the professional feeling
that the common law is the legal order of nature, that its doctrines
in an idealized form are natural law and that its actual rules are
declaratory of natural law. This mode of thinking is to be found in
all professions and is a result of habitual application of the rules
of an art until they are taken for granted. In law it is fortified by
the theory of natural law which has governed in our elementary books
since Blackstone, was taught to all lawyers until the present century,
and is assumed in much of our judicial decision. Later it was
strengthened by the theories of the historical school which ruled in
our law schools in the last quarter of the nineteenth century and
taught us to think that growth must inevitably follow lines which
might be discovered in the Year Books. These things co-operated with
the temper of the last century and the instinctive aversion of the
lawyer to change, lest in some unperceived way a door be opened to
magisterial caprice or to the personal equation of the judge. Thus
some thought of consideration, whatever it was, as inherent in the
very idea of enforceable promises. Others assumed that it was a
historically developed principle by which the future evolution of the
law of contracts must be governed. Many others simply thought that it
was dangerous to talk of change. And yet change has gone on rapidly,
if subconsciously, until the present confused mass of unsystematized
and unsystematizable rules has resulted. The second circumstance
operating to keep alive the requirement of consideration is a more
legitimate factor.

Nowhere could psychology render more service to jurisprudence than in
giving us a psychological theory of _nuda pacta_. For there is
something more than the fetish of a traditional Latin p