These largest waves of variation are broken by lesser ones extending overperiods of months. On these come others severally having a week or two'sduration. And were the changes marked in greater detail, we should see thesmaller undulations that take place each day and the still smaller ones whichbrokers telegraph from hour to hour. The whole outline would show a complicationlike that of a vast ocean-swell, having on its surface large billows, whichthemselves bear waves of moderate size, covered by wavelets, that are roughenedby a minute ripple. Similar diagrammatic representations of births, marriages,and deaths, of disease, of crime, of pauperism, exhibit involved conflictsof rhythmical motions throughout society under these several aspects.
There are like traits in social changes of more complex kinds. Both inEngland and on the Continent the actions and reactions of political progressare now generally recognized. Religion has its periods of exaltation anddepression -- generations of belief and self-mortification, following generationsof indifference and laxity. There are poetical epochs, and epochs in whichthe sense of the beautiful seems almost dormant. Philosophy, after havingbeen awhile dominant, lapses for a long season into neglect, and then againslowly revives. Each concrete science has its eras of deductive reasoning,and its eras in which attention is chiefly directed to collecting and colligatingfacts. And that in such minor phenomena as those of fashion, there are oscillationsfrom one extreme to the other, is a trite observation.
As may be foreseen, social rhythms well illustrate the irregularity thatresults from combination of many causes. Where the variations are those ofone simple element in national life, as the supply of a particular commodity,we do indeed witness a return, after many involved movements, to a previousstate -- the price becomes what it was before: implying a like relative abundance.
But where the action is one into which many factors enter, there is nevera complete recurrence. A political reactIon never brings round just the oldform of things. The rationalism of the present day differs widely from therationalism of the last century. And though fashion from time to time revivesextinct types of dress, these always reappear with decided modifications. §88. Rhythm being thus manifested in all forms of movement, we havereason to suspect that it is determined by some primordial condition to actionin general. The tacit implication is that it is deducible from the persistenceof force. This we shall find to be the fact.
When the prong of a tuning-fork is pulled on one side by the finger, someextra tension is produced among its cohering particles, which resist anyforce that draws them out of their state of equilibrium. As much force asthe finger exerts, so much opposing force arises among the cohering particles.
