You will find that not only is your body constantly doing things because your mind wills that it should do them, but that your body is incessantly doing things simply because they are the expression of a pa.s.sing thought.
The law that _Every idea tends to express itself in some form of bodily activity_, is one of the most obviously demonstrable principles of human life.
Bear in mind that this is but another way of expressing the second of our first two fundamental principles of mental efficiency, and that we are engaged in a scientific demonstration of its truth so that you will not confuse it with mere theory or speculation.
To recall these fundamental principles to your mind and further impress them upon you, we will restate them:
I. _All human achievement comes about through some form of bodily activity_.
II. _All bodily activity is caused, controlled and directed by the mind._
PHYSIOLOGICAL EVIDENCE OF MENTAL MASTERY
CHAPTER V
PHYSIOLOGICAL EVIDENCE OF MENTAL MASTERY
[Sidenote: Introspective Knowledge]
We have been considering the relationship between mind and body from the standpoint of the mind. Our investigation has been largely introspective; that is to say, we simply looked within ourselves and considered the effects of our mental operations upon our own bodies. The facts we had before us were facts of which we had direct knowledge. We did not have to go out and seek them in the mental and bodily activities of other persons. We found them here within ourselves, inherent in our consciousness. To observe them we had merely to turn the spotlight into the hidden channels of our own minds.
[Sidenote: Dissection and the Governing Consciousness]
We come now to examine the mind"s influence upon the body from the standpoint of the body. To do this we must go forth and investigate. We must use eye, ear and hand. We must use the forceps and scalpel and microscope of the anatomist and physiologist.
[Sidenote: Subordinate Mental Units]
_But it is well worth while that we should do this. For our investigation will show a bodily structure peculiarly adapted to control by a governing consciousness. It will reveal to the eye a physical mechanism peculiarly fitted for the dissemination of intelligence throughout the body. And, most of all, it will disclose the existence within the body of subordinate mental units, each capable of receiving, understanding and acting upon the intelligence thus submitted. And we shall have strongly corroborative evidence of the mind"s complete control over every function of the body._
Examine a green plant and you will observe that it is composed of numerous parts, each of which has some special function to perform. The roots absorb food and drink from the soil. The leaves breathe in carbonic acid from the air and transform it into the living substance of the plant. Every plant has, therefore, an anatomical structure, its parts and tissues visible to the naked eye.
[Sidenote: What the Microscope Shows]
Put one of these tissues under a microscope and you will find that it consists of a _honeycomb of small compartments or units_. These compartments are called "cells," and the structure of all plant tissues is described as "cellular." Wherever you may look in any plant, you will find these cells making up its tissues. The activity of any part or tissue of the plant, and consequently all of the activities of the plant as a whole, are but the combined and co-operating activities of the various individual cells of which the tissues are composed. _The living cell, therefore, is at the basis of all plant life._
[Sidenote: The Little Universe Beyond]
In the same way, if you turn to the structure of any animal, you will find that it is composed of parts or organs made up of different kinds of tissues, and these tissues examined under a microscope will disclose a cellular structure similar to that exhibited by the plant.
_Look where you will among living things, plant or animal, you will find that all are mere a.s.semblages of cellular tissues._
Extend your investigation further, and examine into forms of life so minute that they can be seen only with the most powerful microscope and you will come upon a _whole universe of tiny creatures consisting of a single cell_.
[Sidenote: The Unit of Life]
Indeed, it is a demonstrable fact that these tiny units of life consisting of but a single cell are far more numerous than the forms of life visible to the naked eye. You will have some idea of their size and number when we tell you that millions may live and die and reproduce their kind in a single thimbleful of earth.
_Every plant, then, or every animal, whatever its species, however simple or complicated its structure, is in the last a.n.a.lysis either a single cell or a confederated group of cells._
All life, whether it be the life of a single cell or of an unorganized group of cells or of a republic of cells, has as its basis the life of the cell.
For all the animate world, two great principles stand established.
First, that _every living organism_, plant or animal, big or little, develops from a cell, and is itself a composite of cells, and that the cell is the unit of all life. Secondly, that _the big and complex organisms have through long ages developed out of simpler forms_, the organic life of today being the result of an age-long process of evolution.
What, then, is the cell, and what part has it played in this process of evolution?
To begin with, a cell is visible only through a microscope. A human blood cell is about one-three-thousandth of an inch across, while a bacterial cell may be no more than one-twenty-five-thousandth of an inch in diameter.
[Sidenote: Characteristics of Living Cells]
Yet, small as it is, the cell exhibits all of the customary phenomena of independent life; that is to say, it nourishes itself, it grows, it reproduces its kind, it moves about, and _it feels_. It is a _living, breathing, feeling, moving, feeding thing_.
The term "cell" suggests a walled-in enclosure. This is because it was originally supposed that a confining wall or membrane was an invariable and essential characteristic of cell structure. It is now known, however, that while such a membrane may exist, as it does in most plant cells, it may be lacking, as is the case in most animal cells.
The only absolutely essential parts of the cell are the inner _nucleus_ or kernel and the tiny ma.s.s of living jelly surrounding it, called the _protoplasm_.
[Sidenote: The Brain of the Cell]
The most powerful microscopes disclose in this protoplasm a certain definite structure, a very fine, thread-like network spreading from the nucleus throughout the semi-fluid alb.u.minous protoplasm. It is certainly in line with the broad a.n.a.logies of life, to suppose that in each cell the nucleus with its network is the brain and nervous system of that individual cell._
All living organisms consist, then simply of cells. Those consisting of but one cell are termed unicellular; those comprising more than one cell are called pluricellular.
The unicellular organism is the unit of life on this earth. Yet tiny and ultimate as it is, every unicellular organism is possessed of an independent and "free living" existence.
[Sidenote: Mind Life of One Cell]
To be convinced of this fact, just consider for a moment the scope of development and range of activities of one of these tiny bodies.
"We see, then," says Haeckel, "that it performs all the essential life functions which the entire organism accomplishes. Every one of these little beings grows and feeds itself independently. It a.s.similates juices from without, absorbing them from the surrounding fluid. Each separate cell is also able to reproduce itself and to increase. This increase generally takes place by simple division, the nucleus parting first, by a contraction round its circ.u.mference, into two parts; after which the protoplasm likewise separates into two divisions. The single cell is able to move and creep about; from its outer surface it sends out and draws back again finger-like processes, thereby modifying its form. Finally, the young cell has feeling, and is more or less sensitive. It performs certain movements on the application of chemical and mechanical irritants."
[Sidenote: The Will of the Cell]
The single living cell moves about in search of food. When food is found it is enveloped in the ma.s.s of protoplasm, digested and a.s.similated.
The single cell has the _power of choice_, for it refuses to eat what is unwholesome and extends itself mightily to reach that which is nourishing.
[Sidenote: The Cell and Organic Evolution]
Moebius and Gates are convinced that the single cell possesses _memory_, for having once encountered anything dangerous, it knows enough to avoid it when presented under similar circ.u.mstances. And having once found food in a certain place, it will afterwards make a business of looking for it in the same place.
And, finally, Verworn and Binet have found in a single living cell manifestations of _the emotions of surprise and fear_ and the rudiments of _an ability to adapt means to an end_.