Here’s an interesting quote from William Walker Atkinson:

““Concentration” is a word derived from two Latin words, ie., “con,” a prefix meaning “to;” and “centrum,” meaning “center” or “fixed central point.” The two words combined mean, literally, “to bring to a common point; to focus,” etc. Thus the word “Concentration” is seen to mean, literally, “the act or state of bringing to a fixed point or focus.”

Borrowing an analogous illustration from physical science, we readily see that the highest forms of energy, force or power are manifested by bringing the force to a focus, center, or common point, thereby directing to that point the entire energy employed, instead of allowing it to become dissipated over a larger area. The electricity generated by a battery or dynamo, if allowed to diffuse itself over a large surface manifests but a small degree of the power that may be obtained from it by compelling it to discharge itself from a small point of focus.

The same is true regarding the power of steam, which manifests great power by being forced to discharge itself through a small point or opening instead of being permitted to spread itself widely in the air. The same law applies to gunpowder, which manifests force by its gases being compelled to escape through the small gun-barrel instead of spreading in all directions, which it would do if unconfined.

Another familiar example is that of the sun-glass, or “burning-glass,”· which brings the rays of the sun to a common point or focus, greatly intensifying the heat and light by reason thereof.

The occult masters have ever impressed upon their pupils the importance and necessity of acquiring the power of Mental Concentration, and all trained and developed occultists have practiced and persevered toward this end, the result being that some of them attained almost miraculous mental powers and influence. All occult phenomena is caused in this way, and all occult power depends upon it. Therefore the student of Mental Influence should devote much thought, time and practice to this most important branch of the subject.

It is a fact known to all students of mental phenomena that very few persons possess more than a very small degree
of concentration. They allow their mental forces to become scattered and dissipated in all directions, and obtain little or no results from the same. In the degree that a man is able to concentrate, so is he able to manifest mental power. A man’s power of mental concentration is to a great extent his measure of greatness.

The trained occultist will concentrate upon a subject or object with a wonderful intensity, seemingly completely absorbed in the subject or object before him, and oblivious to all else in the world. And yet, the task accomplished, or the given time expired, he will detach his mind from the object and will be perfectly fresh, watchful and wide-awake to the next matter before him. There is every difference in being controlled by involuntary attention, which is a species of self-hypnotization, and the control of the attention, which is an evidence of mastery.

The secret of Mental Concentration lies in the control of the Attention. And the control of the Attention lies in the exercise of the Will.”

On this last sentence we can clearly see the relation of Concentration and Will.

Concentration is always under the control of the Will and that’s why when you train concentration, you are automatically training your Will, and vice-versa. When you train your Will, you are improving your concentration power simply because it will become easier for you to focus your attention on something.

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