If something has a life of its own, we mean that we have little control over it even though we should - it seems to make its own path. For example, "I threw the frisbee to Brian, but it had a life of its own and flew over the fence". This doesn't have to refer only to physical objects.
A hall of mirrors is a metaphor to compare something with the hall of mirrors you see at carnivals/funfairs. It's hard to explain, so look at this pic: http://sidebyside.stanford.edu/photo...g/mirrors1.jpg . I'm not sure, though, what exactly the article means in this context, but there you go.
Student or Learner