三世書 - "Book of Three Lives" (not sure if the translation is correct or not), it is a book widely believed by Chinese as a reference in fortune telling. The most basic premise of this book is based on your name, birthday and time, to tell what kind of person you are in your 'past' life, how your current life is gonna be, and what your 'next' life will be. Certainly, it is not gonna be acceptable for people who doesn't believe in this sort of things and people who doesn't accept the concept of reincarnation, i.e. most Christians. For more information, for those who can read Chinese, please refer to this good article for further details.
I thought about the concept of knowing our past life and next life to be quite ridiculous. I do believe in reincarnation, but the thing is that we can change who we were in our past life regardless who or what we are. If we did good things, we may benefit from them due to karma and vice versa. We just have to accept them, knowing that doesn't help. Like some folks lost their limbs, if they find out the reason is because they chopped someone else's limbs, what can they do this life? If they already lost their limbs, that's it! If they've not, then they should be careful like everyone else. There is a belief that we should do good this life, so we can:
1. Compensate/offset the sins from past lives and current life
2. To accumulate good deeds, so we will be better off next life
I believe that just doing good can make us feel good, that's already good enough to motivate us to continue. Thinking too much about the above just make us too 'calculative'. That may take away the fun or good feelings for doing good deeds.
On the other hand, knowing what will be in next life is also stupid. First, if we believe in karma, things have not been finalized or all set unless we are gonna kill ourselves in next minute. So, there are still plenty of opportunity for changes one way or the other. So, telling you something so definite for next life, like you will be a beggar, a policeman, etc. It is just plain stupid! Cos, just in our current life, we change jobs all the time. Even in the Chinese history, the first emperor of Ming Dynasty had been a monk, a beggar, a thief before end up became an emperor. So, how do we know what stage our life the book is telling?
I do think that consulting fortune-tellers or involve in such activities are very tempting. I did that myself once before. However, I think we should get a grib of our life in our own hands and make the best out of it in our current life. The old lesson of not doing warm to oneself and the others should be a good enough life-long motto. Just try our best and there shouldn't be much regret. That's what I believe in.