I'm a big fan of Alan Watts' "The Wisdom of Insecurity." I've read this book several times and have written about it in numerous blog posts.
(You can search for the posts via the Google box in the right sidebar.)
Here's an article about a core message in that book, letting go: "Alan Watts: Anxiety, Enlightenment, and the Wisdom of Insecurity." Thanks to a Church of the Churchless visitor for sending me a link to the piece.
Excerpts to whet your appetite for reading it:
Throughout the history of civilization individuals have had access to myths which conveyed the sense that life was meaningful and secure – that human beings have a central place in the universe, an importance in the grand scheme of things.
With the rise of science these myths have been penetrated and dissolved. Fewer and fewer individuals find it possible to believe in them, and thus more and more are left standing alone in the void, facing the abyss – forced to figure out the meaning of life and their place in the universe without any external support.
...He [Watts] proposes another solution to the problem – a total and comprehensive reorientation in our way of living via “letting go”. We can let go of our need to feel secure, of our desire for life to be meaningful and to make sense. We can “let go” of all our beliefs which keep us confined and chained to a certain limiting worldview. We can “let go” of our attachment to life and death. Doing so is not easy and requires a transformation of consciousness and attitude, but in the eyes of Watts the time is perfect for such a transformation.
“Letting go” is so difficult because we have an innate tendency to grasp onto things. Because we are aware that everything flows and what we have now will at some point in the future be taken from us, we try to turn the things we’re attached to into stone. We hold too tightly to our loved ones and relationships, we do anything we can to retain our youthfulness as we age, and we grasp onto our beliefs as if they foretold the secrets of the universe, and thus remain rigid and closed minded.
This attempt to grasp onto things doomed to fail – for the universe flows on incessantly and indifferently to our wishes. The attempt to grasp on to things, to make the impermanent permanent, therefore goes against the very nature of life itself. Life is always changing and in flux, and any attempt or desire to make it otherwise is futile and foolish.