[Evgeny]

There are roughly three stages in extra-personal development.

I'm interested to learn some more. Is it your personal classification or do you base it on some research, literature etc.? Could you recommend something to read on a subject of extra-personal development?

[avindroth]

This is my personal classification.

If I had to trace my thoughts, I would point to Lord Chesterfield, Neil Strauss, and Dale Carnegie, in that order.

Also lots of efforts to change people's (read: friends) behavioral patterns. I think, especially for psychology, most valuable insights come from experience, not books. Read the books, and apply the principles.