I have always enjoyed the writings of Francis Schaeffer. I believe one of the revealing statements from Schaeffer deals with what he called a “divided field of knowledge.” He spoke of a dichotomy that has taken place in the fields of science, logic and reason and the areas of theology, philosophy and the arts. He called the scientific/reasoning realm the ‘downstairs’ and the theology/philosophy realm was called the ‘upstairs’. The downstairs can make statements concerning truth and verifiable facts. The upstairs is separated from reason and logic. The downstairs man is determined by forces he cannot control. The upstairs man is free but irrational.
Now what does this mean to us today? If we carry these views to their conclusion, we end up with an inability to state that we have reasoned out our faith. The atheist who relies on the downstairs for his worldview will not accept the views of those in the upstairs because he says that they cannot be empirically verified. But the atheist will not even allow himself the right to investigate the claims of the believer because he rules them out without even looking into them. The upstairs man may simply state that his beliefs are a matter of simple faith which will not impress in any way the downstairs man because he will feel that this is a cop out. And sometimes it is. Often we have not reasoned out our faith. We just believe. And this is why some find it hard to defend their faith.
Of course, there is another possibility. Why not realize that the complete man has no need for such a dichotomy? Why not allow that our faith can be reasonable and that it is up for investigation? We are not to simply believe without reason. Faith is reasonable. The complete man is free to seek evidence in support of his worldview claims. I am sure no one wants to believe anything without reason. In Christianity, we are not asked to do that. God has given us reasoning minds for a purpose and a world that can be investigated. He provided ‘proofs’ of His existence through His creation and through Jesus Christ. So no need for an upstairs/downstairs division. Our reason and our faith are complementary. We exist as both reasoning people and people of faith. Designed in the image of God, we are both natural and spiritual beings. Any attempt to divide the the man and segregate the reasoning and the spiritual is to lose what it means to be fully human.