I was....10...... I think, but this was just in music lessons with the rest of the class. I wasn't really interested, but equally It wasn't like there was some burdgeoning talent waiting to burst forth. Looking back I could probably convince myself either way really. But it probably doesn't matter. I guess I just want someone to look into the future and say "you will learn to pay bass above a basic level, you will not be wasting your time and money".
Thanks for your reply though, it's given me more to think about!
Out of interest, how old were you when you first started playing your instruments?