I just found a RJ quote... - Edit 1
Before modification by Etzel at 28/07/2010 12:22:12 PM
Linda: Since the ability to channel seems to be primarily linked to the soul, if a Channeler is gentled/stilled, will this affect his/her soul in a [future] life as well, as in, will the ability to Channel still be lost?
RJ: No.
Neptune: I think Linda is asking if the soul is immortal in Jordan's world.
Moderator: So...is it??
RJ: Yes, the soul is immortal.
RJ: No.
Neptune: I think Linda is asking if the soul is immortal in Jordan's world.
Moderator: So...is it??
RJ: Yes, the soul is immortal.
This would suggest that normally nothing can destroy a soul (maybe with the exception of the DO breaking free). Souls can only be corrupted.