Man from a psychological standpoint of development is not what he should be. He does not possess the self-mastery, the self-directing power of concentration that is his by right.
He has not trained himself in a way to promote his self-mastery. Every balanced mind possesses the faculties whose chief duties are to engineer, direct and concentrate the operations of the mind, both in a mental and physical sense. Man must learn to control not only his mind but his bodily movements.
When the controlling faculties (autonomic) are in an untrained condition, the impulses, passions, emotions, thoughts, actions and habits of the person suffer from lack of regulation, and the procedure of mental concentration is not good, not because the mind is necessarily weak in the autonomic department of the faculties, but because the mind is not properly trained.
When the self-regulating faculties are not developed the impulses, appetites, emotions and passions have full swing to do as they please and the mind becomes impulsive, restless, emotional and irregular in its action. This is what makes mental concentration poor.
When the self-guiding faculties are weak in development, the person always lacks the power of mental concentration. Therefore you cannot learn to concentrate until you develop those very powers that qualify you to be able to concentrate. So if you cannot concentrate one of the following is the cause:
1. "Deficiency of the motor centers." 2. "An impulsive and emotional mind." 3. "An untrained mind."
The last fault can soon be removed by systematic practice. It is easiest to correct.
The impulsive and emotional state of mind can best be corrected by restraining anger, passion and excitement, hatred, strong impulses, intense emotions, fretfulness, etc. It is impossible to concentrate when you are in any of these excited states.
These can be naturally decreased by avoiding such food and drinks as have nerve weakening or stimulating influences, or a tendency to stir up the passions, the impulses and the emotions; it is a very good practice to watch and associate with those persons that are steady, calm, controlled and conservative.
Correcting the deficiency of the motor centers is harder because as the person's brain is undeveloped he lacks will power.