Ishmael by Daniel Quinn is one of the more thoughts provoking books that I have read in a while.   It is a book on philosophy framed as a discussion between an unlikely teacher and a pupil we can all related to.  There are several core ideas presented in the book:

1) Past performance is no guarantee of future returns.  Just because something has survived for many years does not mean that it will continue to do so.   Examples from the early days of flight are given to convince us of this.  Hopeful inventors with machines meant to fly being thrown off of cliffs.  They fly for a while, but regardless of how much effort the pilot expends, they will not stay in the air.  Machines like in this video: www.youtube.com/watch?v=8y3fIr4dVYE

2) The web of life is being trimmed and cut away so that it only supports man’s needs.  If an animal or plant does not help us then it is eliminated.  The robust web is being reduced to a fragile chain that needs only be broken at a few places to cause the entire system to collapse.

The book goes into more details and explains these concepts in more details.   Take a look at Ishmael by Daniel Quinn.