Page:Popular Science Monthly Volume 24.djvu/351

Rh of the children of efficient parents. It therefore follows that, although we can not trace the control absolutely to effort in the individual, we can still find a part of the difference accounted for in the efforts of a line of ancestors, or in parents whose special aptitudes, perhaps attained directly by work, are united with magnifying effect in one of their children. If we go back of the effective qualities of men, we encounter the unfathomable fact of the persistence of force; for the most important characteristic of these effective qualities is a certain mechanical motive power. It may be possible to definitely separate the force in men into the presence or absence of different kinds of it in a line of ancestors, but ultimately we are obliged to say that the first impulse took place for the same reason that the earth persists in its course round the sun, or for the same reason that motion appears to be an inevitable attribute of matter. Of course this is not accounting for it. It is simply reducing the question to a point of fact beyond which further investigation is apparently useless. In estimating our power of control, the right method is to start with the qualities existing, or latent, and then proceed to their effects. We may say, with Herbert Spencer, that special forms of thought-force were built up through processes of action and adjustment, but, as involved or noticed in his conclusions, this only dissolves the existing special manifestations of force into a general but at the same time unaccountable force.

While the enormous magnitudes and forces in nature remind us of our helplessness, it is yet clear that the tendency to master distant facts is constantly stimulated by natural phenomena. We ought not to be discouraged by the fact that exceptional events are not always classified or reduced to order by us—their connection is often lost, owing to our limited grasp of duration—nor by the truth that as natural phenomena recede from us we are more conscious of problems beyond the circumstances or surroundings which we partly control. Many apparent disconnections gradually lead us away from the series close at hand. The heavenly bodies, for example, manifest so much variation in movement and brightness, that men are led to undertake increasingly difficult or more delicate tasks of calculation, as in estimating the distances of a Centauri, Sirius, Vega, and other stars. Another result is, that attempts are made to form at least a theoretical idea of the physical conditions of suns and planets through knowledge attained by means of the spectroscope. The conclusions thus reached are necessarily imperfect because based upon fragmentary data, but the mental tendency to inquire is with scientific minds inevitable, because there are always appearing, with every increase of telescopic power, other stars beyond those last discovered.

It thus appears that while the high aims of Plato and Aristotle find