The word "atma" means the same as Brahman but is used in a different context. If atma is the space in a pot, then Brahman is the space outside of it. Of course, the quality of space within a pot is no different from the quality of space outside a pot. If the pot is broken, we don't say the space within the pot disappears or merges with the outside space, because space—unlike water or other medium—cannot be cut, divided or separated. Space is always whole no matter appearances of it being otherwise.
Similarly, atma is pure awareness associated with an individual. When the body-mind ends its cycle, it becomes recycled material just like everything else in the universe. However, awareness remains untouched—and not as "David's awareness," "Susan's awareness," "John's awareness," etc. but as the awareness principle.
Atma is also sometimes likened to how electricity works with a light bulb in the way it vivifies a body-mind. A light bulb is only as good as the electrical current keeping it on. Atma's special relationship with the body-mind will forever frustrate scientists because atma isn't an object and therefore, cannot be perceived with the senses or verified with instruments.
Another meaning of atma is "breath," from the verb-root 'at' = to breathe." Like a wind instrument, atma breathes air into the flute, clarinet or oboe to create a unique sound. Without the breath, the instrument is inert without expression.
If we examine the nature of atma, there are five salient features:
Atma is not a part, product or property of the body
Atma exists on a different order of reality than the body. What affects the body doesn't affect atma, just like what affects a pot never affects the space within the pot. Bodies come and go, but atma always remains the same because atma is that which is beyond all objects, including time and even space.
It is an independent factor that pervades and enlivens the body
Unlike the body, atma is not dependent on anything for its existence. As with a computer desktop, what is inert matter (the computer) apparently comes to life provided electricity. However, the electricity is not dependent on the hardware or software. Furthermore, the same electricity that enlivens a computer desktop is the same electricity that powers a blender, hair dryer, television, etc.
It is not limited by the boundaries of the body
Although atma is awareness associated with a body, it is never contained by it. Again, it's only an appearance that the space within a pot is contained, because space is indivisible.
It continues to exist even after the body dissolves
Atma is that which comes before the body and remains after. There's a cognitive shift when one realizes that consciousness doesn't come out of the body but rather, the body comes out of consciousness. Just like space, all objects come out of and resolve back into consciousness. To use our pot metaphor again, we can get rid of the pot but not the space. Space is that which is before, during and after the pot.
It is not born nor does it die. It survives the death of the body.
This goes back to the point made earlier about there being no "David's awareness," "Susan's awareness," etc. There is only one awareness, thus, atma is impersonal. At death, the pot space apparently merges with the outer space, but any idea that there is plurality is only an appearance.
Lastly, atma is often referred to as the Self—my true essence shining as pure, attributeless, limitless awareness. [from Facebook posting]
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