Number! surely there can be nothing mysterious here; no "law" to be
discovered about one, two, three? Well, the next time you shake hands,
ask the man what he feels. A hand. Then ask further and he will feel
five fingers. Now ask rightly and he will feel any number of distinct
spots of pressure. But the real pressures were practically the same
all through. Why, then, did he feel first one, then five, then eight,
ten, or a dozen? So with the objects we become acquainted with through
any of our senses! Why does the same bit of nature now stand before us
"one tree," and now a myriad of leaves and branches? Why do the same
outer groupings fall into such different inner groupings? Why does not
the result of each little nerve of the millions continually played on
in eye, ear, and skin stand out by itself, and we have so many million
feelings?
To explain this: the first time a child opens his eyes he sees, as
Professor James says, but "one big, blooming, buzzing confusion." Not
till some "whole" (knife) be broken up into parts (blade, handle) and
each part be mentally perceived _in immediate succession the one after
the other_ can the idea of "twoness" ever be possible to that child.
The "twoness" is a feeling of distinct nature apart from the two terms
(blade, handle). It rises from the "shock of succession." It is one of
the "modified states" wrought by one element on another, which we
studied in our first experiment. Once lodged in the mind, the feeling
may be remembered and reawakened, like any other. Thereafter the two
parts or terms may come before the mind, awaken this feeling of
twoness, and _now_ stand side by side, simultaneously and numerically
separate.
These are the primary laws of number perception. Our experiments
illustrate and prove them. Though the nerves lying under a needle
point are really several in number, the pressure on them is commonly
felt as "one prick." The area is so small that usually, through life,
all the nerves have been pressed together. They have not been split up
and pressed enough times in succession among themselves for a memory
of "twoness" to have been developed among them. But, by proper
manipulation, not unlike some of the processes of hypnotism, yet
perfectly normal, the "twoness" of some other group of nerves can be
yoked to the feeling resulting from the pressure of a particular
needle point. Thereupon the one needle will feel like two, as
distinctly and clearly as any real two.
[Illustration: MEASURING THE TIME REQUIRED FOR VARIOUS MENTAL ACTS.]