What Dan Rea says is absolutely true, but if you are conversing with a creationist, you can not avoid replying either. I am therefore suggesting something.
It is very unfortunate that the believers resort to every sort of gimmick to oppose science and to prove that it is wrong, but all their gimmics are only negative. This is true of the above logic also.
if the supernatural exists, it must be naturally evident and explainable, that is, reduceable to the natural.
If a supernatural exists, it must have a purpose for its existence, distinct from the purpose of nature. Supernatural is not required to perform the same functions that nature performs. Therefore, first the distinct functions of the supernatural must be clearly defined, then it must be seen without doubt that only the supernatural is performing these functions, and nobody else. The supernatural has no reason to interfere in the nature’s duties and has no reasons to violate the nature’s rules. If a supernatural exists, then it has no reason for hiding itself, human beings must be directly be able to perceive its existence. Above all, those who believe in a supernatural should not exhibit a complex about science and should take the responsibility to independently and perceptibly demonstrate the presence of the supernatural. Instead, they merely resort to gimmicks of every kind, like the one below, with words.
Nature is all there is.
Science can discover all truth about nature.
Therefore, science can explain everything.
Therefore, if the supernatural existed, it would be explainable by science.
If it is explainable by science it is natural.
(Therefore, either the supernatural does not exist or it is merely natural.)
Therefore, nature is all there is.
This is circular reasoning and therefore invalid."
This should actually read as follows:
Nature is all there is.
Science can and will discover all truth about nature.
Therefore, science can and will eventually explain everything.
Therefore, if the supernatural exists, it will be explained by science.
If it is explained by science it is only natural and not supernatural.
Therefore, there is no supernatural.
The believers are experts in circular logic. They say, miracles show that god exists and miracles are there because god exists.
One man's "magic" is another man's engineering. "Supernatural" is a null word.
-- Robert A. Heinlein
Fossil records are layered in various strata that accumulate over time. Tracing back through those layers comparing variance against carbon dating demonstrates that species changed over longs periods of time. You don't find the same animals in the various layers.
Creationists will attack Carbon dating, declaring it as unreliable and spout off some crap about the flood resulting in deep layers of mud whereas the heavier animals sank towards the bottom. This of course flies in the face of even high school science experiments, but Creationists don't care. They just look for any excuse to dismiss scientific knowledge, so they don't have to dig any deeper. They know that their parishioners won't.
As for the stuff about "similarities in genetic data" having to do with a common creator, this just demonstrates this person has no understanding of genetics or organic chemistry (I'm not a scientist, I just play one on the Internet). They rely on ignorance again. "That sounds logical" is all a creationist needs to reaffirm their beliefs. As soon as they really crack it open an do the work, it all fall apart.
If you haven't already seen them, I'd suggest Thunderf00t's youtube series "Why People Laugh At Creationists". He confronts many of these straw-man arguments directly.
"Science bitches! It works."
The evidence for evolution is astounding, it is so vast that it is impossible to truly convey it in a Facebook discussion. If I were you I would buy Richard Dawkins book "The Greatest Show on Earth" and go through the book chapter by chapter because it very well summarizes the evidence for evolution. In return he can do the same with any creationist book of his choice with you. If you do it chapter by chapter I'm pretty sure you do not have to go on for very long.
Alternatively, you could sum show him the evidence from the E. coli experiment conducted by Lenski. If I had to ever present a single proof for evolution, this would be it.
The Catholic Church has accepted evolution as a fact in the early nineties, apparently god waited some time to convey that truth to his disciples when the evidence could not be ignored any longer.
Francis Collins is a prime example of a religious person who has no issues whatsoever to accept evolution as a fact and to hold strongly to his religious beliefs.
I kinda admire the man to be honest, his religious faith does not seem to hold him back in advancing scientific understanding.
"One does not need to deny the fossil record or genetic data to accept creation, merely one interpretation of that data."
Given these two interpretations, why choose #2?
1. provided by science because of evidence
2. provided by religion because of ancient texts that contradict evidence
"you are assuming a basic premise of naturalism and refusing to allow any alternative a priori both philosophically and idealogically."
False, even Dawkins admits to being only "almost certain" there is no god. God is welcome to show him/herself at any time (oops that'd be nature). If we can't perceive "god" with nature, how do we go about perceiving her/him?
A friend of mine is convinced Jesus visited her personally and touched her on the shoulder. An otherwise normal smart person. WTH?
The evidence of evolution is voluminous, no doubt, but the creationists keep finding non-existant errors in it. Everubody is not an expert in science of evolution. My belief is that instead of confronting them with science, we should logic to defeat their arguments.
What does it mean?
"We just have different worldviews." A typical copout.
Our worldview is to take the evidence and see where it leads us and what we can learn from it. Their worldview is to either ignore the evidence or to cherry-pick it to support and reinforce the conclusion they have already chosen as being the one and only possible conclusion.
So long as they wish to remain mired in their irrationality, there will be no conversation and no chance for a meeting of the minds.
Faith Is No Reason.
The creationists want to run with the rabbit and hunt with the hound. If they want to prove creation, they must produce their own scientific data. They can not own the data science has produced.