Here’s an interesting quote by William Walker Atkinson:

“To the reader who has had no experience along the lines of Mental Concentration, it may seem like a very easy task to focus the mind upon a subject, and then hold it there firmly and fixedly. But a little practice will undeceive such a person, and will bring him to a realizing sense of the difficulty of the task.

The mind is a very restless thing, and its tendency is to dance from one thing to another, darting here and there, soon tiring of continued attention, and like a spoiled child, seeking a new object upon which to exercise itself.

On the other hand, many people allow their minds to concentrate (involuntarily) upon whatever may strike the fancy, and, forgetting everything else. They give themselves up to the object attracting their attention for the moment, often neglecting duties and important interests, and becoming day-dreamers instead of firm thinkers.

This involuntary concentration is a thing to be avoided, for it is the allowing of the attention to escape the control of the will.

The Mental Concentration of the occultists is a very different thing, and is solely in control of the will, being applied when desirable, and taken off or inhibited when desirable.

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.”

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