Is knowledge, science, understanding what we are, where we are and what has and will be.
Self knowledge is part of this, but mysticism as comfortable and fun as it may be has no part. What does it create do or contribute? What is the point of a heaven if all you do is stand around all day and worship. That'd get bloody boring rather quickly I'd hope, both for the one being worshiped and those doing so. And who cares if you might be reincarnated as a bacteria it's hardly useful to worry about that, your not going to remember.
Instead why not seek out real knowledge, how to help others or ones self. Seek to extend your days and minimise your impact while expanding or helping to expand our knowledge.
As in the end, all that may well remain of us is our contribution to knowledge, which should it reach the necessary levels, may end up sustaining us and allow us to remain as we seek to expand it and seek out new wonders.
After all the universe doesn't care about you and chance ain't going to hand you a free survival card just because you believe it should. Learn and grow, expand your capabilities and knowledge and you might just manage to stay ahead of the reaper.
But don't forget to bring the other living things with you, or you'll end up cutting your own throat with out even noticing.