What is life all about? What is our purpose on this world? It is a great question and gets us thinking. Einstein tried to answer this but failed when Light was found to act both as a wave and particle. That became the hard problem of Science and still is to most scientists.
Enter Tom Cambell, A Physicist by background who had the unusual opportunity to go out of body (OBE) and experience the consciousness. Once he got a hang of it, he did it and gathered enough data and evidence to prove an existence of larger consciousness. He went on to explain what Einstein could not and very convincingly. Below is his book, My Big TOE (Theory of Everything) available for free. It is a huge read.
For those who dont have that much time, below is a video series where he talks about the theory of everything and the practical application of the same. This series requires you to invest around 15 hours of your time but surely this should be an eye opener and a life changer.