condition of persons and things.' Later in the same article we are told that 'he that has money has the profit not actually, but only virtually; and it may be hindered in many ways.'[4] It seems quite clear from these passages that Aquinas admitted the right to compensation for a profit which the lender was hindered from making on account of the loan; but that, in the circumstances of the time, the probability of making such a profit was so remote that it could not be made the basis of pecuniary compensation. The probability of there being a _lucrum cessans_ was thought small, but the justice of its reward, if it did in fact exist, was admitted. [Footnote 1: II. ii. 78, 2, ad. 1.] [Footnote 2: Rambaud, _op. cit._, p. 67.] [Footnote 3: II. ii. 62, 4.] [Footnote 4: _Ibid._, ad. 1 and 2.] This interpretation steadily gained ground amongst succeeding writers; so that, in spite of some lingering opposition, the justice of the title _lucrum cessans_ was practically universally admitted by the theologians of the fifteenth century.[1] [Footnote 1: Ashley, _op. cit._, p. 99. _Lucrum cessans_ was defined by Navarrus as 'amissio facta a creditore per pecuniam sibi non redditam' (Endemann, _Studien_, vol. ii. p. 279).] Of course the burden of proving that an opportunity for profitable investment had been really lost was on the lender, but this onus was sufficiently discharged if the probability of such a loss were established. In the fifteenth century, with the expansion of commerce, it came to be generally recognised that such a probability could be presumed in the case of the merchant or trader.[1] The final condition of this development of the teaching on _lucrum cessans_ is thus stated by Ashley:[2] 'Any merchant, or indeed any person in a trading centre where there were opportunities of business investment (outside money-lending itself) could, with a perfectly clear conscience, and without any fear of molestation, contract to receive periodical interest from the person to whom he lent money; _provided only_ that he first lent it to him gratuitously, for a period that might be made very short, so that technically the payment would not be reward for the use, but compensation for the non-return of the money.' At a later period than that of which we are treating in the present essay the short gratuitous period could be dispensed with, but until the end of the fifteenth century it seems to have been considered essential.[3] [Footnote 1: Ashley, _op. cit._, vol. i. pt. ii. p. 402.] [Footnote 2: _Ibid._] [Footnote 3: Ashley, _op. cit._ vol. i. pt. ii. p. 402; Endemann, _Studien_, vol. ii. pp. 253-4; Cleary, _op. cit._, p. 100.]