他们是算不对的，比如说有几个孩子，姓什么叫什么。但有些事情，they can either manipulate the rhetorics or make it vauge to make it sound plausible. but they ARE very good at screening people by their age, look, behavoir, etc in order to improve the accuracy of their guesses.

比如说，他们会跟你说，你早年曾经经历坎坷，有一次丢了一件很贵重的东西，有一次被人委曲，被人误解，被人欺负，有一次你曾经痛不欲生，有一次惊险的经历，但你化险为夷等等诸如此类的话。

试想，人一生那么多年，那么多天，总会发生一些这样的事，they manipulate you thoughts to make you back-fit their words to the past life events. 谁一生没有几次惊险的经历？of course you 化险为夷, otherwise you won't be standing in front of them, but can they tell what kind of event was that and when it happened?

还有一些interesting tricks and maths, 很有意思。我以前从来不信算命的，也从来就没考虑果这个问题。有次在静安寺门口见到无数多算命的，那天下午没事，坐在静安公园里想了一下午，and figured out the algorithm and science(for the lack of better phrases) of this ancient trade. 有空再写篇雄文详述.