The cessation of thought is the one thing which the believer in intellect as the highest term of our evolution cannot contemplate with equanimity. To master the fleeting randomness of thought by regulating the intellectual powers and thinking consecutively and clearly is an ideal he can understand. But to still this higher development of thought seems to him the negation of human activity, a reversion to the condition of the stone. Yet it is certain that it is only by the stilling of the lower that the higher gets full play. So long as the body and vital desires are active the mind is necessarily distracted and it is only when the body is forgotten and the vital part consents to quietude that a man can concentrate himself in thought and follow undisturbed the consecutive development whether of a train of reasoning or a train of inspiration. Not only is this so, but the higher faculties of the mind can only work at their best when the lower are quieted.
If the accumulations in the chitta, the recording part of the mind, are continually active, full as it is of preconceived ideas, prejudices, predilections, the great mass of previous sanskaras, the reflective mind which is ordinarily called the reason is obstructed in its work and comes to false conclusions. It is essential for the faculties of the reason to be freed as far as may be from this ever increasing accumulation of thought-sensations good and bad, false and true which we call mind - manas. It is freedom which is called the scientific spirit. To form no conclusions which are not justified by observation and reasoning, to doubt everything until it is proved but to deny nothing until it is disproved, to be always ready to reconsider old conclusions in the light of new facts, to give a candid consideration to every new idea or old idea revived if it deserves a hearing, no matter how contradictory it may be of previously ascertained experience or previously formed conclusion, is the sceptical temper, the temper of the inquirer, the true scientist, the untrammelled thinker.
The interference of prejudgment and predilection means bondage and until the higher mind has shaken off these fetters, it is not free; it works in chains, it sees in blinkers. This is as true of the materialist refusing to consider spiritualism and occultism as it is of the religionist refusing to consider Science. Freedom is the first requisite of full working power, the freedom of the higher from the lower. The mind must be free from the body if it is to be purified from the grossness which clogs its motions, the heart must be free from the obsessions of the body if love and high aspiration are to increase, the reason must be free from the heart and the lower mind if it is to reflect perfectly, - for the heart can inspire, it cannot think, it is a vehicle of direct knowledge coloured by emotion, not of ratiocination. By (a) similar process if there is anything higher than the reason it can only be set free to work by the stillness of the whole mind not excluding the reflective faculties. This is a conclusion from analogy, indeed, and not entirely binding until confirmed by experience and observation.
But we have given reason in past articles for supposing that there is a higher force than the logical reason - and the experience and observation of Yoga confirm the inference from analogy that the stillness of the mind is the first requisite for discovering, distinguishing and perfecting the action of this higher element in the psychology of man.
Excerpt from the book Essays Divine and Human by Sri Aurobindo