One of Keller’s enlightening discussions centers on the question of doubt. In my own book I make the observation that a skeptic is “a thoughtful person, usually of above average intelligence, who tends to place doubt on a higher moral plane that belief.” Keller offers a startling explanation for this phenomenon by pointing out that, “All doubts, however skeptical and cynical they may seem, are really a set of alternate beliefs.” Sincere doubt about the existence of God necessitates a system of other beliefs about the origin and purpose of the universe and life that is even more difficult to prove than the existence of God. A person’s doubt that there can be only one way to God is based on his or her own concept of ‘fairness’ and the nature of God. These concepts can also not be proven empirically.
Keller concludes that believers and skeptics alike need to take a second look at their doubts. Believers who honestly confront their own doubts will find their faith strengthened through the process. He points out that, “Faith without doubt is like a human body without any antibodies.” If we don’t acknowledge and resolve our doubts, we will be ill prepared for the hard times that will test our faith. On the other hand, skeptics should look more closely at their doubts and examine the beliefs underlying them. This process might lead them to concede that their own ‘faith’ in these beliefs may be as difficult to logically prove as the believer’s beliefs. Both groups would benefit from this process and be better able to talk to each other with less suspicion.
I agree with Keller on this last point, but must reassert my underlying interest in this discussion. When I put some of my doubts on hold and went from skepticism to Christ, my life took a radical and positive turn. I hope to show other skeptics how such a step of faith can be possible in their lives. A new look at the nature of doubt and belief seems like an important starting point in this process.
 Keller, Timothy. The Reason for God: Belief in an Age of Skepticism. New York: Dutton(Penguin Group), 2008.