Every typical African have this mindset of "seeing is believing" before believing anything. If an African is being told something, especially in the rural parts, they'll always refer the phrase "seeing is believing" that means they'll have to witness it or have someone that has witnessed similar situation before they'll eventually believe it. Many of us have been in similar situation or experienced it before.
This idiomatic expression was first recorded in this form in 1639 before it became very usual and easily used in Africa as a continent. Africans are very reluctant in believing a thing unless they see it.
I really don't know whether it's a bad mindset or it's a good one. But i think on both sides, they're equivalent. If this is true, we won't believe anything from the Bible because we were not there were the Bible was written, we were not there when most of the activities happened in the Bible, in fact we won't even have to believe about the existence of Christ.