This topic has been pretty thoroughly hashed out before. Search the forum for "breath of life" if you want to read over it again.
My position is based (among many things) on believing Job knew what he was talking about when he said:
Job 3:11 Why died I not from the womb? why did I not give up the ghost when I came out of the belly?
Job 10:18 Wherefore then hast thou brought me forth out of the womb? Oh that I had given up the ghost, and no eye had seen me!
Job knew he had a spirit (ghost) as an unborn. Who am I to argue with that?