Concentration of the mind can only be developed by watching yourself closely. All kinds of development commence with close attention. You should regulate your every thought and feeling.
But the person that can center his mind on any problem, no matter what it is, and remove any unharmonious impressions has strength of mind. Concentration, first, last and all the time, means strength of mind.
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.
