Page:The Autocrat of the Breakfast-Table (1858) Holmes.djvu/209

 much beyond the reach of outside influences as if they were governed by clock-work. The animal functions, as the physiologists call them, in distinction from the organic, tend, in the process of deterioration to which age and neglect united gradually lead them, to assume the periodical or rhythmical type of movement. Every man's heart (this organ belongs, you know, to the organic system) has a regular mode of action; but I know a great many men whose brains, and all their voluntary existence flowing from their brains, have a systole and diastole as regular as that of the heart itself. Habit is the approximation of the animal system to the organic. It is a confession of failure in the highest function of being, which involves a perpetual self-determination, in full view of all existing circumstances. But habit, you see, is an action in present circumstances from past motives. It is substituting a vis a tergo for the evolution of living force.

When a man, instead of burning up three hundred pounds of carbon a year, has got down to two hundred and fifty, it is plain enough he must economize force somewhere. Now habit is a labor-saving invention which enables a man to get along with less fuel,—that is all; for fuel is force, you know, just as much in the page I am writing for you as in the locomotive or the legs that carry it to you. Carbon is the same thing, whether you call it wood, or coal, or bread and cheese. A reverend gentleman demurred to this