I like very much to read RW Emerson and here is what he was writing about soul:
"The soul is not an organ but it animates and exercises all the organs, It not a function like like the power of memory, of calculation, of comparison but it uses these functions as hands and feet. ~The soul is not a faculty but light, the soul is not the intellect or will but the master of the intellect and will. It is the background of our being in which they lie."
I think that this is one of the most accurate descriptions of the soul that I have read. Especially the part where he describes the soul as a light. I think it is the divine spark sitting deep inside each of us. A spark we may choose to give lots of air and let it become a flame or even a fire that gives light not only to ourselves but also to our fellow humans as well.
If we could live a life governed by soul, I think it would be soooo good.