It has already been explained that the actual method of practice in Vipassana Meditation is to note or to observe or to contemplate the successive occurrences of seeing, hearing or feeling at six points or sense doors. However, it will not be possible for a beginner to follow up all successive incidents as they occur because his Mindfulness, Concentration and Spiritual Knowledge (sati, samadhi and nana) are still very weak. Also these incidents occur very swiftly. Seeing seems to occur at the time of hearing, hearing seems to occur at the time of seeing, it seems that both seeing and hearing occur simultaneously. It seems that three or four incidents of seeing, hearing, thinking, and imagining usually occur simultaneously. It is not possible to distinguish which occurs first and which follows next because they occur so swiftly. In actual fact, seeing does not occur at the time of hearing nor does hearing occur at the time of seeing. Such incidents can occur one only at a time. A Yogi who has just begun the practice and who has not sufficiently developed mindfulness, concentration and Spiritual Knowledge will not, however, be in a position to observe all these incidents singly as they occur in serial order. A beginner need not therefore follow up many things, but should instead start with a few things. Seeing or hearing occurs only when due attention is given. If one does not pay heed to any sight or sound, one may pass the time mostly without any occasion of seeing or hearing. Smelling occurs rarely. Experience of taste occurs only at the time of eating. In the cases of seeing, hearing, smelling and tasting, the Yogi can note them when they occur.
However, body impressions are ever present,they usually exist quite distinctly all the time. During the time that one is sitting, the body impressions of stiffness or the sensation of hardness, in this position are distinctly felt. Attention should therefore be fixed on the sitting posture and a note made as “Sitting”.
Sitting is an erect posture of the body consisting of a series of physical activities which are induced by the consciousness consisting of a series of mental activities. Just as an inflated rubber ball maintains its round shape through the resistance of the air inside it, so also is the posture of sitting, in which the body is kept in an erect posture through the continuous process of physical activities. A good deal of energy will be required to pull up and keep in an erect position such a heavy load as this body. People generally assume that the body is lifted and kept in the position by means of sinews. This assumption is correct in a sense because sinews, blood, flesh and bones are nothing but physical elements. The element of stiffening which keeps the body in an erect posture belongs to the material group and arises in the sinews, flesh and blood throughout the body like the air in a rubber ball. The element of stiffening is vayo–dhatu, the air element. The body is kept in the erect position by the presence of the Air Element in the form of stiffening, which is continually coming into existence. At the time of heavy drowsiness one may drop flat, because the supply of new materials in the form of stiffening is cut off. The state of mind in heavy drowsiness or sleep is Unconsciousness.
During the course of Unconsciousness mental activities are absent, and for this reason the body lies flat during sleep or heavy drowsiness. During waking hours strong and active mental activities are continually arising, and because of these there arises a series of Air Elements in the form of stiffening. In order to know these facts it is essential to note attentively as “Sitting” This does not necessarily mean that the body impressions of stiffening should be particularly searched and noted. Attention need only be fixed on the whole form of sitting posture, that is, the lower portion in a bending circular form and the upper portion in an erect posture.