You are living daily, in the midst of all manner of thought impulses which are reaching your subconscious mind, without your knowledge. Some of these impulses are negative, some are positive. You are now engaged in trying to help shut off the flow of negative impulses, and to aid in voluntarily influencing your subconscious mind, through positive impulses of desire.
When you achieve this, you will possess the key which unlocks the door to your subconscious mind. Moreover, you will control that door so completely, that no undesirable thought may influence your subconscious mind.
Everything which man creates, begins in the form of a thought impulse. Man can create nothing which he does not first conceive in thought. Through the aid of the imagination, thought impulses may be assembled into plans. The imagination, when under control, may be used for the creation of plans or purposes that lead to success in one’s chosen occupation.
All thought impulses, intended for transmutation into their physical equivalent, voluntarily planted in the subconscious mind, must pass through the imagination, and be mixed with faith. The “mixing” of faith with a plan, or purpose, intended for submission to the subconscious mind, may be done only through the imagination.
* Source: Think and Grow Rich by Napoleon Hill