Re: Should a belief in reincarnation ...
As to karma, while I accept that what you sow you also reap, I'm not so sure how much follows one from life to life. Sure there's cell memory - otherwise there wouldn't be adaptation and evolution and survival. However, the definition of Karma that says we are punished for the things we do is just another version of Judeo-Christianity's go to heaven or go to hell.
If you accept that part of the human package is free will, how can there be punishment? It's not logical to say, here, do what you will, BUT there's a list of rules you know nothing about that you have to figure out or you'll burn for it. Free will is an absolute; we either have it or we don't.
Philosophies that say in ignorance we can damn ourselves to hell or an awful next life are not life affirming or constructive. They are merely methods of control through fear. And who is out there to say we're done paying for our transgressions? That the karmic checkbook has been balanced? I mean really!
We are all evolving and growing; would you punish a freshman for making the mistakes of a freshman, for not being and having the wisdom of a senior?
No, I think we are counseled as to what challenges will help us grow and become seniors, and thus we enter our next life with the challenges appropriate to our level of development. We aren't punished, except perhaps, by our own life review when we see clearly what we've sowed, and that is often punishment enough.