The Doctrine and Practice of Yoga
Concentration signifies the state of being at a centre (con and centrum). Applied to thought, it is the act of bringing the mind to a single point. Each human being must practise concentration subjectively and objectively. In other words, each human being aims with more or less precision at concentration on a point within and a point without his own world. Concentration "without" is illustrated when you devote all your attention upon Nature, such as learning a trade, a profession, a science, an art or some form of business. This is Evolution, outgoing or positive mental energy. I shall call this Objective Concentration. Concentration "within" implies the withdrawing of attention from the external world and the placing of mind on "God," "Spirit," "Heaven," "Religion," "Peace," "Nirvana," "Eternity," etc. This is Involution, i.e., incoming or negative energy.
When Objective Concentration alone is practised, you develop into a hard-headed, practical man of the world or a successful man of business. You are keen and shrewd. The world is a very matter-of-fact thing to you. You cannot think of anything else beyond money-making and pleasures and worldly affairs. You are a "worldling of the world," very clever, rich, and a master along your own lines. But spiritually you are an imbecile, worse than a baby. This is the Objective Mind—the "deepest immersed in matter, literally made of the dust." "It is the brain of worldly wisdom, common sense, prudence, methodical arrangement, order, discipline, classification, the skill and knowledge of the expert in any branch or department of art or science." This side of the mind is well developed in Scientists, Mathematicians and Businessmen, etc. Where it is not guided by the Subjective Mind, it can only see diversity and difference and is the slave of Maya—the slayer of the Real.
Subjective Concentration is seeking the Kingdom of Heaven within you. "God is Spirit and they that worship Him must worship in Spirit and Truth." LAPLACE, the great astronomer, asserted that he had swept the heavens with his telescope and found neither God nor Heaven. Yes, poor LAPLACE! He looked for God objectively instead of subjectively.
The Kingdom of God comes not with 'observation' but it is 'within' you. The be-all and the end-all of religion is the practice of Subjective Concentration. The performance of objective work by the human organism necessitates expenditure of energy and at last death, because all Objective Concentration means 'going from' the Absolute centre—God—and hence it expends Spiritual Energy. Subjective Concentration means 'coming to' the centre and hence it husbands and recuperates this energy. Now nature is motion to and from, and Spirit—the centre of Life. This two-fold motion constitutes what is known as polarity—Evolution and Involution—negative and positive. At the negative pole life becomes involved, i.e., 'wrapped up' in form. At the positive pole life 'evolves' or becomes expressed in nature....