Please accept my apologies. I posted a couple of minutes ago and recommended a book of philosophical poetry by Dr. Muhammad Iqbal titled "Asrar - i- Khudi (The Secrets of Self)". I have rewritten this post and removed the link to the book because it feels to me that this work is too religious in content and it does not seem appropriate to present it here.
Sorry for taking up space on this thread I hope you guys will excuse my intrusion on your interesting discussion and forgive me for it.
Anyways, look up the book on Google (I believe its in public domain) if your are not bothered by being confronted with a very strong religious philosophy. I felt it was a little too strong hence the rewrite of the post.
Asim