Sri Aurobindo
Letters of Sri Aurobindo
06. Transformation of the Mind
To reject doubts means control of one’s thoughts – very certainly so. But the control of one’s thoughts is as necessary as the control of one’s vital desires and passions or the control of the movements of one’s body – for the yoga, and not for the yoga only. One cannot be a fully developed mental being even, if one has not a control of the thoughts, is not their observer, judge, master,– the mental Purusha, manomaya puruṣa, sākṣī, anumantā, īśvara. It is no more proper for the mental being to be the tennis-ball of unruly and uncontrollable thoughts than to be a rudderless ship in the storm of the desires and passions or a slave of either the inertia or the impulses of the body. I know it is more difficult because man being primarily a creature of mental Prakriti identifies himself with the movements of his mind and cannot at once dissociate himself and stand free from the swirl and eddies of the mind whirlpool. It is comparatively easy for him to put a control on his body, at least on a certain part of its movements; it is less easy but still very possible after a struggle to put a mental control on his vital impulsions and desires; but to sit like the Tantric yogi on the river, above the whirlpool of his thoughts, is less facile. Nevertheless, it can be done; all developed mental men, those who get beyond the average, have in one way or other or at least at certain times and for certain purposes to separate the two parts of the mind, the active part which is a factory of thoughts and the quiet masterful part which is at once a Witness and a Will, observing them, judging, rejecting, eliminating, accepting, ordering corrections and changes, the Master in the House of Mind, capable of self-empire, sāmrājya.
The yogi goes still farther; he is not only a master there, but even while in mind in a way, he gets out of it as it were, and stands above or quite back from it and free. For him the image of the 
factory of thoughts is no longer quite valid; for he sees that thoughts come from outside, from the universal Mind or universal Nature, sometimes formed and distinct, sometimes unformed and then they are given shape somewhere in us. The principal business of our mind is either a response of acceptance or a refusal to these thought-waves (as also vital waves, subtle physical energy waves) or this giving a personal-mental form to thought-stuff (or vital movements) from the environing Nature-Force. It was my great debt to Lele that he showed me this. “Sit in meditation,” he said, “but do not think, look only at your mind; you will see thoughts coming into it; before they can enter throw these away from your mind till your mind is capable of entire silence.” I had never heard before of thoughts coming visibly into the mind from outside, but I did not think either of questioning the truth or the possibility, I simply sat down and did it. In a moment my mind became silent as a windless air on a high mountain summit and then I saw one thought and then another coming in a concrete way from outside; I flung them away before they could enter and take hold of the brain and in three days I was free. From that moment, in principle, the mental being in me became a free Intelligence, a universal Mind, not limited to the narrow circle of personal thought as a labourer in a thought factory, but a receiver of knowledge from all the hundred realms of being and free to choose what it willed in this vast sight-empire and thought-empire. I mention this only to emphasise that the possibilities of the mental being are not limited and that it can be the free Witness and Master in its own house. It is not to say that everybody can do it in the way I did it and with the same rapidity of the decisive movement (for, of course, the latter fullest developments of this new untrammelled mental power took time, many years) but a progressive freedom and mastery of one’s mind is perfectly within the possibilities of anyone who has the faith and the will to undertake it.