“When attention is moved in a sweeping manner from one part of the body to the next, can the mind really stay on one particular spot, on one particular sensation long enough to observe its arising, unexpected change and passing away? It seems to me that attention would be scattered in this way, and there would be no opportunity to observe a particular sensation continuously, before moving on to observe yet another sensation.”
Sensations arise and disappear at a high frequency rate. With our poor levels of attention, we can only detect great changes, but in spite of that they are still there, you can feel the change despite the few seconds you spent observing before going to the next sensation. Once you become more and more concentrated, the “same” feelings begin to disarm and you can detect more textures inside them. That procedure continues to unfold over and over again, until it is supposed that the meditator reach the state of bhanga dissolution, an important point in the progress of insight called “Visuddhiñana-katha”:
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5. Knowledge of Dissolution (bhanga-ñana)
6. Awareness of Fearfulness (bhayatupatthana-ñana)
7. Knowledge of Misery (adinava-ñana)
8. Knowledge of Disgust (nibbida-ñana)
9. Knowledge of Desire for Deliverance (muncitu-kamyata-ñana)
10. Knowledge of Re-observation (patisankhanupassana-ñana)
11. Knowledge of Equanimity about Formations (sankhar’upekkha-ñana)
12. Insight Leading to emergence (vutthanagamini-vipassana-ñana)
13. Knowledge of Adaptation (anuloma-ñana)
14. Maturity Knowledge (gotrabhu-ñana)
15. Path Knowledge (magga-ñana)
16. Fruition Knowledge (phala-ñana)
17. Knowledge of Reviewing (paccavekkhana-ñana)
18. Attainment of Fruition (phalasamapatti)
19. The Higher Paths and Fruitions