2. _Only those things and actions that are in some causal relation to gratifications can have value to man._ This proposition of theory is demonstrated every hour in practical life. The business man always is trying to trace a causal relation between things that do not and cannot themselves directly satisfy wants, and things that do. The vineyard has no value to Tantalus, unable to reach its fruit. A captive, chained to a rock, attaches value only to the things within his reach. Men living in savagery and ignorance starve amid the possibilities of plenty. Chained by their ignorance and improvidence to a little spot of earth, they do not see clearly, either in time or space, the economic relations about them. [Sidenote: Values of things distant in time] 3. _Man's foresight and knowledge enable him to think of many periods at once, and thus his felt dependence on goods extends over a series of future productive agents._ In order to simplify the problem, we have spoken of the economic man as living only in and for the moment. If he had no more knowledge, memory, or imagination than is necessary to compare goods here, only present goods could have value to him. Even the higher animals, and much more the savages, rise above that level of improvidence. With increased intelligence the economic life of man expands, and he attaches importance to things which at the present moment have not, and cannot have, the slightest influence on his immediate gratification. The extension of man's view works a momentous change in his economic estimates. Of the thousands of forms of matter in the world, only a comparatively few ever will make an immediate gratifying impression on man's senses. But many of them are so connected in his thought by chains of association with pleasures or uses, that almost instinctively and most intensely he attaches an importance to them. In most cases it would require close thought to see that the service attributed directly to them was but a reflection of that performed by some other good. Thus, more and more, the estimates placed by men on goods come to depend on knowledge and foresight, and not on immediate impressions and feelings. [Sidenote: Goods related in varying degrees to psychic income]