Dean Nelson, the author of an upcoming book on Polkinghorne (see below) wrote a nice piece for USA Today in which he touches on the subject of certainty and how good science (and religion) can do without it. I think his assertions are on the right track and I look forward to the book.

People of science are motivated to believe certain things as they proceed with their experiments, and people of faith are motivated to believe certain things as they proceed with their beliefs. Living with doubt leaves one open to additional discovery, both in science and faith.

Article here.

Quantum Leap: How John Polkinghorne Found God in Science and Religion