_Conditions affecting the Importance of a Future Income._--The importance of a future income may be large because of the prospective helplessness or poverty of the one who expects to enjoy it. A workman may save at a great present cost to himself in order to provide for old age or sickness, in which case the income from the savings, and often the savings themselves, would be the means of averting a great calamity. To make one's self secure against privation in the future is worth more than to add to one's comforts in the present. If a certain minimum amount were needed to avert starvation at the end of a man's life, he should secure that amount at all hazards, however much that may trench on his present comforts. Now, as the amount which he can have at the end of his life depends largely on the rate of interest which his savings will earn, during such time as they may remain in a productive shape, it will take more positive abstinence on his part to keep himself from starvation when the rate of interest is low than it will when the rate is high. If there were no interest at all, he would have to put by from his income his entire old-age fund. If the rate were a hundred per cent per annum, taking a very small part of the fund out of the income of his active years would suffice, since the fund itself would earn the remainder. Is the income which is provided for the future to be treated as a variable amount in addition to some other income, or is it to be regarded as a fixed amount, which is needed for some definite purpose? On the answer to this question depends the entire issue as to whether a low rate of interest or a high one affords the larger incentive for saving. _Future Incomes More or Less Fixed usually Needed._--Recent writers have called attention to the fact that in many cases saving has the providing of a definite future income in view. The owner of a landed estate, who intends to leave it to a son, may try to provide from his rents an endowment which will save from want or from an unhappy approach to want his daughters and his younger sons. He might accomplish this, indeed, without any present saving by putting rent charges or mortgages upon his land, but that would trench on the income which his heir can derive from it. It would reduce the establishment which the heir can maintain and cause him to fall out of the class to which his father has belonged. Rather than do this, the present owner will usually reduce the present standard of living of the entire family and try to make sure that its future standard shall not fall below the one thus established. It seems better to maintain the somewhat lower standard through a series of generations than to make the present mode of living more luxurious at the cost of unclassing one's self and one's heirs at a later date.