Buddha's path is to experience reality

Observing, observing you will reach the stage when you experience that the entire physical structure is nothing but subatomic particles: throughout the body, nothing but kalapas (subatomic particles). And even these tiniest subatomic particles are not solid. They are mere vibration, just wavelets. The Buddha's words become clear by experience: Sabbo pajjalito loko, sabbo loko pakampito. The entire universe is nothing but combustion and vibration. As you experience it yourself you experience that the entire material world is nothing but vibration. We have to experience the ocean of infinite waves surging within, the river of inner sensations flowing within, the eternal dance of the countless vibrations within every atom of the body. We have to witness our continuously changing nature. All of this is happening at an extremely subtle level. These kalapas (subatomic particles) according to the Buddha, are in a state of perpetual change or flux. They are nothing but a stream of energies, just like the light of a candle or an electric bulb. The body (as we call it), is not an entity as it seems to be, but is a continuum of matter and life-force coexisting.
As you experience the reality of matter to be vibration, you also start experiencing the reality of the mind: vinnana (consciousness), sanna (perception), vedana (sensation) and sankhara (reaction).

http://www.buddhanet.net/bvk_study/bvk21d.htm
(Sourced from 'Buddha's path is to experience reality' by S N Goenka OCT 95 Vipassana english news letter, 'Samma Samadhi' April 95 hindi Vipassana patrika, discourses of Sayagyi U Ba Khin-Sayagyi U Ba Khin Journal-VRI Igatpuri)