The Stages of Vipassana - 1st stage of vipassana nana

The first stage of vipassana nana (insight) is knowledge of the difference between nama and rupa (nama-rupa-pariccheda-nana).
Maha-kusala citta nana-sampayutta arises and clearly distinguishes the difference between the characteristic of nama and the characteristic of rupa as they appear one at a time. The objects constituting “the world” appear as devoid of self. At that moment there is no atta-sanna (wrong remembrance of self)  which used to remember or perceive realities as a “whole,” conceived as “the world.” There begins to be right remembrance of the realities which appear as anatta. Satipatthana should continue to be aware of all kinds of nama and rupa, in addition to those realised at the moment of vipassana nana. When there is awareness of realities, panna should consider again and again anatta-sanna penetrated at the moment of vipassana nana. Otherwise atta-sanna, which has been accumulated for a long time in the cycle of birth and death, cannot be eradicated.