The guest on this edition of Crosstalk has written a fascinating and captivating book with strong evidence that we have a wonderful and wise creator, as Scripture points to in Romans 1:20.E. Howard Callahan is a retired chemical engineer who spent years working in the fields of chemistry and biology. His research and development work revealed to him that God indeed made the world. He's done R&D work on aloe vera, learning of its many uses in humans, also R&D for an anticancer drug-delivery system. He also helped develop and manufacture an artificial scab for very large wounds. As a Christian, he's spent over 60 years studying the Bible and how it applies to our everyday lives and holds a master's degree in theology. He is author of the newly released, Instincts by Design: Instinctive Behaviors of Humans & Animals in Creation.