It is crucial to understand what non-dual truth is. It is not yoga, and it's not some rituals or mantras. Pursuit of truth is the being aware of the fact that, soul/ spirit is the true self, and learn to view and judge the three states on the standpoint of the soul as self.
Non-dual truth is awareness of the true self. The witness of the three states that appear and disappear in succession is not the physical self but the soul/spirit. Thus the soul is the formless substance and witness of all the three states. This isn't easy to assimilate since one is conditioned to view the three states on the standpoint of waking entity. The waking entity is present only in waking experience and it is absent in dream and deep sleep. Therefore, one which witnesses the three states is not the waking entity, but the formless substance of the three states. This has to be mentally grasped by constantly reflecting on the subject to realize the object is mere mirage.
If one is seeking after non-dual truth, he should investigate things in such a way that his consciousness as he investigate is not distracted by what he find, or diffused and scattered; neither is it fixed and set.
The drop and the ocean have been related since ancient times. Likewise, the body and the universe have been deemed to be related. In simple language one can use the terms man and the world [waking/dream]. The latter is a totality comprising not only man but also other beings and material objects within the world.
Every man is related to the world. In order to understand a single individual the whole world will have to be understood and vice versa.
Man and his experience of the world exist within the waking or dream. Man and his experience of the world internally related and interactive that one cannot be interpreted without the other.
Even if an atom is to be understood, the whole world will have to be understood. The one, who knows the true self is the soul/spirit, knows the diversity is mere mirage. And one, who knows the appearance is mere mirage, knows every thing in diversity is spirit. Nothing one can be known without the soul, which is the true self.
In waking or dream all appear separate, but in substance all are one. Self/soul alone is real, the three states are unreal.
