Great answers everyone. Thank you for your responses. I appreciate everyone's perspective, not just Erin's so feel free to respond if you've got something to contribute.
I'd like to take Nneka's response a bit further.
So, would you say that the reason could be summed up as the memories we cling onto from past lifetimes would hinder our conscious development in THIS lifetime? For example, imagine if in one lifetime we drowned and had a massive fear of water due to it. If we kept our memories from lifetime to lifetime, we would continue to be totally afraid of water for 1000's of years just because of something that happened a long time ago.
I've heard that this actually does happen. THat there are repressed memories from other lifetimes that if traumatic enough do stay with our consciousness in this lifetime. For example, I *DO* have a rather unusual fear of water compared to lets say heights. That could mean that in a previous lifetime maybe I drowned, but maybe I haven't fallen off any tall buildings. For example, I'd rather jump out of an airplane and skydive, rather than be in the water with sharks. I know others who are the opposite.
My only challenge with this way of thinking is that it's rather limited. Meaning, surely our "spiritual" selves in all our wisdom could come up with a better way to deal with limiting beliefs and fears from previous lifetimes than to just "nuke the whole hard-drive" of memories. I mean, just the idea of being able to remember yourself being a spiritual being would eliminate most fears for people who fear death due to the fact that they are afraid of ceasing to exist after death.
But, lets say that it does happen that way. We choose to "nuke" our memories in order to descend back to earth and live another life. Would it then mean that anyone a medium communicates with in the "ether" is someone who has not descended back to earth yet, because if they did then their memory would be lost?
Like, lets say that I get Erin to do a reading and as a medium she has no problems communicating with my great grandma Rose (example). So she talks to Rose and gets a bunch of information from her etc. But then after 5 years, Rose decides to go back to earth and reincarnate as a little child in Africa. I get a reading done a few weeks later and I want to re-connect with Rose through Erin. Would Rose now be "unreachable" because her memory has been wiped as she's now a little child in Africa?
Taking the analogy further, lets say the child in Africa dies in 6 months. I get another reading...can I now re-connect with Rose? Or are her memories gone forever because she decided to go back to earth, and her only memories are that of a 6 month old child?
My personal intuitive reasoning tells me that we don't remember because it is a requirement for our lesson here on earth. We choose to forget because remembering that we are indestructible everlasting beings might stifle our growth due to non-urgency.
Imagine the following scenario:
Wife: "Honey, can you please go fix the fence?"
Husband: "Nah, I'm busy watching the game honey..."
Wife: "But it's been broken for years!"
Husband: "Maybe I'll get to it in the next lifetime."
Wife: "But if the dog gets out he'll get hit by a car."
Husband: "That's ok, he'll re-incarnate anyways."
I'm poking fun, but imagine if all the next generation of children being born all of a sudden had memories of who they were from the life before, how would that screw everything up!
You have toddlers learning to talk and naming their murders from their previous lifetime. Would that hold up in court?
Things would get really complicated really fast if we all remembered everything while here on earth.