Mind control is the result of self-discipline and habit. You either control your mind or it controls you… — Napoleon Hill

Mind control is the result of self-discipline and habit. You either control your mind or it controls you. There is no half-way compromise. The most practical of all methods for controlling the mind is the habit of keeping it busy with a definite purpose, backed by a definite plan...Without this control, success is not possible. p. 173

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