Some students make demand that I define what is the meaning of the word "vibration" and state exactly what a vibration is. If I tell you that vibration is an illusion, as sensory perception is known by the soul to be, do you comprehend (limited as all human beings are by the reactions of a series of vehicles, all of them instruments of perception)? If I tell you that vibratory reaction is due to our possessing a mechanism which is responsive to impact, I am answering your question in part, but if this is true, what does it mean to you and from whence comes the impact? If I give you the scientific definition (which you can discover in any good textbook on light, color or sound), I am doing work that you can do yourself, and for that I have no time. In my books are several definitions of vibration, either by inference or defined, and these you might search for, and upon them you might meditate. If I elucidated for you here the relation between the Self and the not-Self, between awareness, that which is aware, and that of which it is aware, I am covering ground which a careful study of the Gita would aid you in comprehending. [372]

Believe me when I assure you that I am not seeking to evade answering any questions, but if I can awaken you to the realization of the necessity for "spiritual limitation" (as it is esoterically called when defining the career of a disciple within the limits of his task) and bring to your attention the need for achieving the goal you set yourself when you started to work, I shall have aided you far more than if I had defined vibration or pointed out to you just how much progress, through what process, you or others had made.