
PRATYAHARA is the first process in the mental part of our task. The previous practices, Asana, Pranayama, Yama, and Niyama, are all acts of the
body, while mantra is connected with speech: Pratyahara is purely mental. And what is Pratyahara? This word is used by different authors in different
senses. The same word is employed to designate both the practice and the result. It means for our present purpose a process rather strategical than practical; it is introspection, a sort of general examination of the contents of the mind which we wish to control:
Asana having been mastered, all immediate exciting causes have been removed, and we are free to think what we are thinking about. A very similar experience to that of Asana is in store for us. At first we shall very likely flatter ourselves that our minds are pretty calm; this is a defect of observation. Just as the European standing for the first time on the edge of the desert will see nothing there, while his Arab can tell him the family history of each of the fifty persons in view, because he has learnt how to look, so with practice the thoughts will become more numerous and more insistent.
As soon as the body was accurately observed it was found to be terribly restless and painful; now that we observe the
mind it is seen to be more restless and painful still. ("See diagram opposite.") A similar curve might be plotted for the real and apparent painfulness of Asana. Conscious of this fact, we begin to try to control it: "Not quite so many thoughts, please!" "Don't think quite so fast, please!" "No more of that kind of thought, please!" It is only then that we discover that what we thought was a school of playful porpoises is really the convolutions of the sea-serpent. The attempt to repress has the effect of exciting. When the unsuspecting pupil first approaches his holy but wily
Guru, and demands magical powers, that Wise One replies that he will confer them, points out with much caution and secrecy some particular spot on the pupil's body which has never previously attracted his attention, and says: "In order to obtain this magical power which you seek, all that is necessary is to wash seven times in the Ganges during seven days, being particularly careful to avoid thinking of that one spot."
from - THE WAY OF ATTAINMENT OF GENIUS