(quote from RealReality.org/Real_Faith_and_Reason_Vol_2_-_Scientia.pdf)
“Then, by the way, the fundamental thing that we disagree on, Mr. Ham, is this nature of what you can prove to yourself. This is to say, when people make assumptions based on radiometric dating, when they make assumptions about the expanding universe, when they make assumptions about the rate at which genes change in populations of bacteria in laboratory growth media, they’re making assumptions based on previous experience. They’re not coming out of whole cloth.” ~ Bill Nye
“assumptions about the expanding universe”
We can’t test assumptions about a supposed “expanding universe,” and contrary to what some people say, no one has observed an “expanding universe.” We do know God has expanded the universe in the past, and we know that by divine revelation. But how does Bill think he knows it’s expanding now? Admittedly, we can observe parts of the universe and assume nonsense. We can start from those observations and move smoothly to assumptions. From these assumptions, we can imagine an “expanding universe.” (Jake Hebert, Ph.D., Big Bang Blowup at Scientific American) Therefore, scientists interpret observations as a story about an “expanding universe,” and those who interpret it this way base this interpretation on assumptions. But Bill’s phrase presupposes a currently “expanding universe” using assumptive language. It’s worse than that. Bill oversimplified the problem. Scientists add more assumptions to the extrapolation of previous assumptions. They then use these assumptions to become dogmatic about their shaky conclusions. They finish with irrational conclusions based on layers of assumptions.
For instance, scientists base all radiometric dating on assumptions. Scientists must assume the conditions at time zero. The scientists who believe in billions of years assume zero contamination over time. They also assume a constant decay rate. They’re extrapolating back in time, but the further they extrapolate beyond what they observe, the more unreliable their calculations become. These scientists may think they’re using sound inductive logic, but they have left reality and spun away into the land of make-believe. They can’t prove any of their extrapolations with observation or experience. If they’re wrong on even one of their assumptions, they deceive themselves and anyone who believes them.