In plain words
every object, every person, even the smallest insects! Among these visible objects the body too is only one object; so how can this body itself be the seer? If that is so, then who indeed is the seer? Fire burns objects and, in doing so, makes them shine. But who is it that sees that the fire, which does the burning and the illuminating, is different from the objects themselves? What is burned is one thing; what burns — the fire — is another. And who is it that knows this? That very knower is the Ātma. Just as fire pervades the whole of the firewood, the Ātma has pervaded the whole of the body. It is precisely for this reason that the body, able to act and endowed with movement, moves about.
At night in a house, the instrument that shows 'this is a thorn,' 'this is a bowl,' 'this is a tray' is the lamp, its light. In just the same way, the eye, which shows 'house,' 'thorn,' 'tooth,' is only an instrument. It is not the Ātma. Without a lamp, the eye cannot see; without the eye, the lamp cannot show anything — neither the house, nor the thorn, nor the bowl, nor the tray can be seen. The eye, an instrument, cannot see without the lamp; the lamp — its light — an instrument, cannot see without the eye. So both are merely instruments of light. Existing as an instrument, the eye sees even its own body by means of itself; and if the very eye that sees is itself an instrument, then how could the body that is seen fail to be an instrument too — what else could it possibly be?
In this world, all the experience that comes through hearing, eating, seeing, touching and smelling belongs to the senses alone. Since the seeing eye is an instrument, the remaining four senses too are merely instruments, but they are not the Ātma. That which keeps these instrumental senses under its own control is the mind. The mind is a thinking faculty — merely another lamp-like instrument. So how could this, too, be the Ātma? It is not the Ātma either.
That which examines and settles what the mind presents to it is Buddhi. This too is merely a determining instrument. Take a small illustration: there is a sharp knife. However sharp that knife may be, of its own accord, by itself, it cannot