Briefly, then, if the conduct is the best possible on every occasion, it follows that as the occasions are endlessly varied the acts will be endlessly varied to suit—the heterogeneity in the combinations of motions will be extreme.
§ 28. Evolution in conduct considered under its moral aspect, is, like all other evolution, toward equilibrium. I do not mean that it is toward the equilibrium reached at death, though this is, of course, the final state which the evolution of the highest man has in common with all lower evolution; but I mean that it is toward a moving equilibrium.
We have seen that maintaining life, expressed in physical terms, is maintaining a balanced combination of internal actions in face of external forces tending to overthrow it; and we have seen that advance toward a higher life, has been an acquirement of ability to maintain the balance for a longer period, by the successive additions of organic appliances which by their actions counteract, more and more fully, the disturbing forces. Here, then, we are led to the conclusion that the life called moral is one in which this maintenance of the moving equilibrium reaches completeness, or approaches most nearly to completeness.
This truth is clearly disclosed on observing how those physiological rhythms which vaguely show themselves when organization begins, become more regular, as well as more various in their kinds, as organization advances. Periodicity is but feebly marked in the actions, inner and outer, of the rudest types. Where life is low there is passive dependence on the accidents of the environment; and this entails great irregularities in the vital processes. The taking in of food by a polype is at intervals now short, now very long, as circumstances determine; and the utilization of it is by a slow dispersion of the absorbed part through the tissues, aided only by the irregular movements of the creature's body; while, such æration as is effected is similarly without a trace of rhythm. Much higher up we still find very imperfect periodicities; as in the inferior molluscs which, though possessed of vascular systems, have no proper circulation, but merely a slow movement of the crude blood, now in one direction through the vessels and then, after a pause, in the opposite direction. Only with well-developed structures do there come a rhythmical pulse and a rhythm of the respiratory actions. And then in birds and mammals, along with great rapidity and regularity in these essential rhythms, and along with a consequently great vital activity and therefore great expenditure, comparative regularity in the rhythm of the alimentary actions is established, as well as in the rhythm of activity and rest; since the rapid waste to which rapid pulsation and respiration are instrumental, necessitates tolerably regular supplies of nutriment, as well as recurring intervals of sleep during which repair may overtake waste. And from these stages the moving equilibrium characterized by such interdependent rhythms, is continually made better by the counteracting of more and more of those actions which tend to perturb it.
So is it as we ascend from savage to civilized and from the lowest among the civilized to the highest. The rhythm of external actions required to maintain the rhythm of internal actions becomes at once more complicated and more complete, making them into a better moving equilibrium. The irregularities which their conditions of existence entail on primitive men, continually cause wide deviations from the mean state of the moving equilibrium—wide oscillations; which imply imperfection of it for the time being, and bring about its premature overthrow. In such civilized men as we call ill conducted, frequent perturbations of the moving equilibrium are caused by those excesses characterizing a career in which the periodicities are much broken; and a common result is that the rhythm of the internal actions being often deranged, the moving equilibrium, rendered by so much imperfect, is generally shortened in duration. While one in whom the internal rhythms are best maintained is one by whom the external actions required to fulfill all needs and duties, severally performed on the recurring occasions, conduce to a moving equilibrium that is at once involved and prolonged.
Of course the implication is that the man who thus reaches the limit of evolution, exists in a society congruous with his nature, is a man among men similarly constituted, who are severally in harmony with that social environment which they have formed. This is, indeed, the only possibility. For the production of the highest type of man can go on only pari passu with the production of the highest type of society. The implied conditions are those before described as accompanying the most evolved conduct—conditions under which each can fulfill all his needs and rear the due number of progeny, not only without hindering others from doing the like, but while aiding them in doing the like. And evidently, considered under its physical aspect, the conduct of the individual so constituted, and associated with like individuals, is one in which all the actions, that is the combined motions of all kinds, have become such as duly to meet every daily process, every ordinary occurrence, and every contingency in his environment. Complete life in a complete society is but another name for complete equilibrium between the co-ordinated activities of each social unit and those of the aggregate of units.
§ 29. Even to readers of preceding volumes, and still more to other readers, there will seem a strangeness, or even an absurdity, in this presentation of moral conduct in physical terms. It has been needful to make it, however. If that re-distribution of matter and motion constituting evolution goes on in all aggregates, its laws must be fulfilled in the most developed being as in every other thing; and his actions, when decomposed into motions, must exemplify its laws. This we find that they do. There is an entire correspondence between moral evolution and evolution as physically defined.
Conduct, as actually known to us in perception, and not as interpreted into the accompanying feelings and ideas, consists of combined motions. On ascending through the various grades of animate creatures, we find these combined motions characterized by increasing coherence, increasing definiteness considered singly and in their co-ordinated groups, and increasing heterogeneity; and in advancing from lower to higher types of man, as well as in advancing from the less moral to the more moral type of man, these traits of evolving conduct become more marked still. Further, we see that the increasing coherence, definiteness, and heterogeneity, of the combined motions, are instrumental to the better maintenance of a moving equilibrium. Where the evolution is small this is very imperfect and soon cut short; with advancing evolution, bringing greater power and intelligence, it becomes more steady and longer continued in face of adverse actions; in the human race at large it is comparatively regular and enduring; and its regularity and enduringness are greatest in the highest.