ception.
There is no doubt that the doctrine of the canonists which impresses
the modern mind most deeply is the usury prohibition, partly because
it is not generally realised that the usury doctrine would not have
forbidden the receipt of any of the commonest kinds of unearned
revenue of the present day, and partly because the discussion of usury
occupies such a very large part of the writings of the canonists. It
may be quite true to say that the doctrine of usury was that which
gave the greatest trouble to the mediaeval writers, on account of the
nicety of the distinctions with which it abounded, and on account of
the ingenuity of avaricious merchants, who continually sought to
evade the usury laws by disguising illegal under the guise of
legal transactions. In practice, therefore, the usury doctrine was
undoubtedly the most prominent part of the canonist teaching, because
it was the part which most tempted evasion; but to admit that is not
to agree with the proposition that it was the centre of the canonist
doctrine.

[Footnote: 1 _Op. cit._, vol. i. pt. ii. p. 399.]

[Footnote: 2 'Bekanntlich war das Wucherverbot der praktische
Mittelpunkt der ganzen kanonischen Wirthschaftspolitik,' _Op. cit._,
p. 8.]

[Footnote: 3 _Studien_, vol. i. p. 2 and _passim_. At vol. ii. p. 31
it is stated that the teaching on just price is a corollary of the
usury teaching. But Aquinas treats of usury in the article _following_
his treatment of just price.]

Our view is that the teaching on usury was simply one of the
applications of the doctrine that all voluntary exchanges of property
must be regulated by the precepts of commutative justice. In one sense
it might be said to be a corollary of the doctrine of just price. This
is apparently the suggestion of Dr. Cleary in his excellent book on
usury: 'It seems to me that the so-called loan of money is really
a sale, and that a loan of meal, wine, oil, gunpowder, and similar
commodities--that is to say, commodities which are consumed in use--is
also a sale. If this is so, as I believe it is, then loans of all
these consumptible goods should be regulated by the principles which
regulate sale contracts. A just price only may be taken, and the
return must be truly equivalent.'[1] This statement of Dr. Cleary's
seems well warranted, and finds support in the analogy which was drawn
between the legitimacy of interest--in the technical sense--and the
legitimacy of a vendor's increasing the