r, admitted by
Scotus, who said that it was lawful to stipulate for recompense when
both the principal and surplus were in danger of being lost[2]; by
Carletus;[3] and by Nider.[4] The question, however, was still hotly
disputed at the end of the fifteenth century, and was finally settled
in favour of the admission of the title as late as 1645.[5]

[Footnote 1: _Ibid._]

[Footnote 2: Cleary, _op. cit._, p. 117.]

[Footnote 3: _Summa Angelica Usura_, i. 38.]

[Footnote 4: _De Cont. Merc._, iii. 15.]

[Footnote 5: Cleary, _op. cit._, p. 117.]

Sec. 6. _Other Cases in which more than the Loan could be repaid_.

We have now discussed the extrinsic titles--_poena conventionalis,
damnum emergens, lucrum cessans_, and _periculum sortis_. There were
other grounds also, which cannot be reduced to the classification of
extrinsic titles, on which more than the amount of the loan might be
justly returned to the lender. In the first place, the lender might
justly receive anything that the borrower chose to pay over and above
the loan, voluntarily as a token of gratitude. 'Repayment for a favour
may be done in two ways,' says Aquinas. 'In one way, as a debt of
justice; and to such a debt a man may be bound by a fixed contract;
and its amount is measured according to the favour received. Wherefore
the borrower of money, or any such thing the use of which is its
consumption, is not bound to repay more than he received in loan; and
consequently it is against justice if he is obliged to pay back more.
In another way a man's obligation to repayment for favour received
is based on a debt of friendship, and the nature of this debt depends
more on the feeling with which the favour was conferred than on the
question of the favour itself. This debt does not carry with it a
civil obligation, involving a kind of necessity that would exclude the
spontaneous nature of such a repayment.'[1]

[Footnote 1: II. ii. 78, 2, ad. 2.]

It was also clearly understood that it was not wrongful to borrow at
usury under certain conditions. In such cases the lender might commit
usury in receiving, but the borrower would not commit usury in paying
an amount greater than the sum lent. It was necessary, however, in
order that borrowing at usury might be justified, that the borrower
should be animated by some good motive, such as the relief of his own
or another's need. The whole question was settled once and for all by
Aquinas: 'It is by no means lawfu