I'm probably not the first to make this conclusion, but when I did, it had a tremendous impact upon my thinking: we are the universe considering itself. In other words, for eons the universe was silent, until consciousness first arose (whether here on Earth or elsewhere, we cannot say), and then that consciousness became the eyes and ears of the universe. In this way, matter gave itself the ability to consider and analyze itself, to learn. With this in mind, how can we not hold consciousness - which may well be a fleeting commodity in the history of the universe - how can we not hold it precious?

I've written about this a few times in the past, including most recently, on my blog:

 http://stribs.blogspot.com/2007_04_01_archive.html