larger amount of future goods. There are numberless illus trations of this type of preference. In the various cases men tioned in the preceding paragraph one would need merely to shift his position in point of time to reverse the order of pref erence. In the summer a quantity of present ice is valued more than the certainty of the same amount the next winter; in the winter present eggs are valued more than the trust worthy promise of an equal number the next spring. So with fruits and grains just before the new crop matures, the fire-engine when the conflagration is under way, the battle ship when the war has begun.
§ 5. Biologic basis for most choice of present use. The different time-periods, present and future, and their different economic situations are brought into comparison either by in stinctive choice (necessarily involving a ratio of comparison), or by conscious choice between the thing actually present and the future good more or less clearly pictured in the imagina tion. To take and enjoy things as soon as the desire arises and the means are present seems to be a fundamental trait of t men. The impulse to seek immediate gratification is rooted deep in man's biologic nature. It is found in the most ele mentary forms of animal life (see Chapter 2, sections 1 and 2) and continues to be a powerful guide to action as higher forms of life evolve. It has in the course of evolution been only slowly modified and supplemented by inhibiting instincts and by reason. This impulse is still dominant in the actions of most men, and is ever ready to reassert itself under unusual temp tations even in prudent natures. With children and savages and with many civilized men the voluntary postponement of the gratification of desire is of very limited character. Powerful and universal impulses work in favor of present gratification ; man's provision for the future occurs only when imagination, reason, habit due to long training, and a strong will to pursue a distant object hold these impulses in 5 It is true that in the social insects (bees and ants) and occasionally among some higher animals (squirrels), the storing of food is an act § 6. Hope and risk as affecting time-preference. Hope is a blessed gift to man to help him bear the ills of life, but hope does not always operate with great discrimination.
Hope of fure provision for future needs encourages the present use of goods, leaving the future to care for itself. As the successive years will bring recurring needs, they will, while health and strength continue, bring also recurring sup plies of goods. If this were the unbroken rule of life, the most economic use of goods would be to consume each year's products as they come. This, indeed, is the firmly fixed habit of life of a large portion of humanity, even under conditions where the results are clearly bad. In many provident and well-to-do families there are persons who are so sheltered from responsibility in caring for the future, that they blindly trust that good things will continue to come in unlimited quantities. Like the young robin with open mouth, ever eager to be fed, they accept unthinkingly the sacrifices of others. Business reverses, the illness or the death of the responsible member of the family, often leave all unprovided for, those in whom prodigality has thus grown into a habit.
The uncertainty of life likewise strengthens the preference for present over future goods. There are two possibilities of loss by waiting, one that the future goods may not be there ("A bird in the hand is worth two in the bush"), and the other that one may not be there himself to enjoy them. ("Eat, drink and be merry, for to-morrow we die.") Life itself is uncertain, all but the present moment. Each of these risks involves a discount on the future uses as compared with the present. So large is this uncertainty of life among sav ages, so many die of accidents and wounds, that many tribes are said to have only the vaguest conception of a natural of instinctive choice and is continued even in circumstances where the least forethought would show the futility of the process. But in man this choice seems to be possible only by the aid of forethought and reason, or of habit acquired by the individual through the earlier exercise of these faculties.
death. In semi-civilized and in rude pioneer days, it was al most the rule to "die with one's boots on." Even in the most regular order of things, to-day's desires have the strongest claims of any desires in one's life, simply because they are the most certain.