The following video is of Ken Wilber, a modern philosophical theorist. It is quite interesting.
The following are books that might interest you by Ken Wilber:
The Integral Vision: A Very Short Introduction to the Revolutionary Integral Approach to Life, God, the Universe and Everything (this has great reviews on Amazon.com)
Integral Life Practice: a 21st Century Blueprint for Physical Health, Emotional Balance, Mental Clairty, and Spiritual Awakening (this recieved great reviews as well on Amazon.com)