The short answer to your question is prediction, verification and discovery.
Consider Tiktaalik for example. Palaeontologists predicted the transitional between fish and amphibious land dweller based on evolutionary theory. They predicted the geological period in which such a transitional should exist if current evolutionary theory and geological principles are indeed correct. They then identified the type of rock and location in which to search for the transitional. Lo and behold they discovered one of the finest examples of transitional fossils ever found.
The chances of just stumbling upon such a find are miniscule.
The discovery was made as a direct result of prediction based on theory. Without the theory the prediction could not have been made. Without the theory being true the chances of the discovery being made are all but impossible.
Real science tests theories via means of prediction and verification. Where theories are verified this leads to new discoveries and new evidence.
All creationism ever does is re-interpret the evidence found as a result of real science undertaken by real scientists. They then insist that all interpretations are equal and that science is as dogmatic as they themselves are. This is nonsense.
Just ask your friend what new physical phenomenon the creationist world has discovered lately. Read up on Tiktaalik and use this as an example and refuse to accept mere re-interpretations of evidence arguments. Ask him why creationists do not test their theories. Ask him why creationists do not make predictions based on their theories. Ask him why creationists do not make discoveries such as Tiktaalik.
Edited by Straggler, : No reason given.
Edited by Straggler, : No reason given.
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