From Margaret J. Wheatley's Eight Fearless Questions -- mentioned on Dave Pollard & Chris Corrigan's sites:
What if your work achieves nothing? Thomas Merton, a great writer and contemplative in the Catholic tradition, said, "Do not depend on the hope of results. You may have to face the fact that your work will be apparently worthless and even achieve no result at all, if not, perhaps, results opposite to what you expect.
"As you get used to this idea of your work achieving nothing, you start more and more to concentrate not on the results but on the value, the rightness, the truth of the work itself. And there, too, a great deal has to be gone through, as, gradually, you struggle less and less for an idea and more and more for specific people. The range tends to narrow down, but it gets much more real. In the end, it is the reality of personal relationships that saves everything."