The most noticeable exception to this rule is only an apparent one. The revenue (_Nutzung_) derived from the use of capital must not be confounded with its partial restoration.[180-3] Thus, for instance, the rent of a house, if the entire capital is not to be sooner or later consumed entirely, must embrace, besides a payment for the use of the house, a sum sufficient to defray the expenses of repairing it, and even to effect a gradual accumulation of capital for the purpose of rebuilding. The risk attending the investment of capital plays a very large part and must be taken into special consideration. If the risk in a business be so great that ten who engage in it succeed and ten fail, the returns of the former, which are more than double those usual in the country, in reality pay, when the ten who failed are taken into the account, only the rate of interest customary in the country. The risk may depend on the uncertainty of the person to whom the capital is confided;[180-4] on the uncertainty of the branch of business in which it is intended to employ it,[180-5] or on the uncertainty of the commercial situation in general; but especially may it depend on the uncertainty of the laws.[180-6] The temporary lying idle of capital, for instance, in dwelling houses at bathing places during the winter season, increases the rate of interest much more than it does the rate of wages in the corresponding case of the lying idle of labor; for the reason that there is something pleasurable in the repose of the latter. (_Senior._) On the whole, the vanity of mankind has an effect upon the rate of interest similar to that which it has on the rate of wages. (See § 168.) It causes the small chances of loss to be estimated below their real value, and the extraordinary chances of gain above it.[180-7] [Footnote 180-1: Compare _Harris_, Essay on Money and Coins, 13. _Per contra, Ganilh_, Dictionnaire analyt., 107. According to _Hermann_, Staatsw. Untersuchungen, 147, a product which withdraws an amount of capital = _a_ from the immediate use of its owner for _n_ months must bring in in its price a surplus, over and above the outlay of capital, which would bear the same ratio to the profit from another product which employed an amount of capital = _b_, _m_ months, that _an_ bears to _bm_.] [Footnote 180-2: The class of bankers, etc. which precisely in the higher stages of civilization is one so highly developed, is called upon to adjust these differences.] [Footnote 180-3: Life annuities and annual revenues, _à fonds perdu_.] [Footnote 180-4: Hence, for instance, good men engaged in industrial pursuits who employ borrowed capital productively pay lower interest than idlers who are suspected of desiring only to spend it in dissipation. High house-rent usually paid by proletarians.]