The Law of the Soul

Do you believe that human beings have souls, and dogs, for example, do not? And if you believe that humans have souls, then must you also believe that in order for the soul to be a soul it must be immortal? Or can the soul be born with us and die with us, never to return, and still be a soul? And if you believe that it must be immortal, then must you also believe that if it is not immortal, then it is just a psyche - the forms of awareness, desiring and imagining that humans share with all other percipient creatures - but certainly not a soul.

And if you believe that every human has a soul, then what is it? What is the soul? And why is it that humans have souls and other percipient and desiring creatures do not?