Old soul
I always hear this as a compliment (i myself have been described by a friend as an old soul), so I dont think it means anything like a simpleton. this is my vote that yes, it means something on the order of wise beyond one's years.
for what its worth,
chris
FYI
how I type:
I have limited use of my left hand, so I have to type one-handed. Therefore, I don't use much punctuation or capitalization, unless I think there will be confusion without it.
Sorry for any inconvenience.
"Old soul" is a term related to reincarnation. According to that belief, an old soul has lived many life-times and has acquired wisdom, knowledge, etc. I googled "old soul" and "reincarnation" and came up with several Web sites including www.angelfire.com/ biz2/metaphysician/reincarnation.html
Your typing is fine.