Then, who really is this I? Fire burns and also brightens. It burns things by heat and brightens them by the light it sheds. Fire is different from the things it acts upon. Now, who is it that knows this truth - the truth that 'fire' and the 'things that it burns' are different? It is the Atma. When a log burns, the fire is present and active in all of it. Similarly, the Atma pervades the entire body, and enables it to perform deeds and to move itself and its limbs.

The light shed by the lamp is the instrument that informs us at night: "This is the cup", "This is the plate". The eye is similar instrument which informs us "This is a house", "This is a thorn", "This is a stone". The eye is not the Atma. In the absence of the lamp, the eye, or, in the absence of the eye, the lamp cannot cognise the house, the thorn, the stone, the cup or the plate. Both the lamp and the eye are media or instruments of 'illumination'.

The instrument, eye, sees the body, where it is situated. The body that is seen cannot therefore be other than a similar instrument. The senses are the experiencers of hearing, tasting, seeing, touching and smelling. When the eye is known as an instrument, the other four senses too have to be recognised as tools. All these senses are under the control of the mind which is their master. Even this mind is being controlled and conditioned by some other master. The mind cannot be the core of man.

The intellect or buddhi examines the information materials offered by the mind. It is the instrument that judges and decides. For example, imagine a sharp knife. However sharp, it cannot cut a fruit on its own initiative. Nor can it cut the thinnest thread by itself. It can do so only when it is held by the hand of some one. The intellect is similar to the knife. It is helpless without the 'I', the Atma which has to wield it.