The soul is the form (in the classical Platonic/Aristotelian sense) of the body. Although every created thing has a form, the substantial form of man is unique. Since man can apprehend eternal things, his mind (soul) must be eternal.
I know there are references in the Bible to body, soul and spirit. I don't have an explanation for them. Perhaps spirit refers to the indwelling Spirit?
Is there a biblical reference for the concept of a soul seperating from the body at death?