Mike asked:
I am currently having a discussion with a Young Earth Creationist who posits that the whole question of science is a philosophical one and that the view on evidence is purely philosophical. I don’t know how to respond to (what I think) is an absurd argument. Do you have any tips?
Answer by Graham Hackett
Many people have had discussions, not only with Young Earth Creationists, but with the whole area of Intelligent Design, and find that they founder and become heated over the role of evidence. The nature of the evidence in religion is mostly testimonial. There is nothing wrong with testimonial evidence per se, but anyone (not just a scientist) is entitled to ask where the testimonial comes from. If the testimonial of (say) one observer is corroborated by the testimony of another, it is still perfectly reasonable to ask what the testimony shows. Professional scientists do this all the time; after all, there are plenty of examples of scientific frauds. Testimonial evidence must be interrogated, that is the scientific position.
Some scientific areas of enquiry, such as applied medicine, are also not without such problems as the downplaying of, or even the total dismissal of evidence. Consider the notorious case of Dr Semmelweis in the 19th century, who presented evidence that the death rate in one hospital ward (where the doctors washed there hands) was much lower the in another, where doctors came straight from the mortuary and did not wash their hands. Semmelweis was regarded as an impertinent upstart, questioning the status of doctors. The evidence was, at the time, disregarded.
Also, many creationists of all varieties are particularly sensitive about the lack of direct, testable evidence for their own positions; the kind of evidence we can interrogate. This is particularly the case with Young Earth and intelligent design. I have searched for peer-reviewed papers in scientific journals which make claims for the findings of creationists, but have found none. Very often, creationists of all stripes restrict their own scientific remarks to attacking the claims of other scientific disciplines. You might like to have a look at some of their responses to the interpretation of carbon dating techniques, which is particularly pertinent to the Young Earth position. There is nothing reprehensible about doing this, but it is surely a weakness in ones position when virtual all of our time is spent on rebuttal and not on proactive argument.
The problem really seems to be, that creationists will eventually reach a point where scientific evidence will no longer do the job they want to do; which is to provide support for their thesis. This is an ancient problem Consider the remark, attributed to Tertullian
“What has Athens to do with Jerusalem?”
Athens was the home of philosophical enquiry, and Jerusalem the home of monotheistic deistic religion. The inference seems clear; the two areas are clear and distinct from each other; they do not relate. St Augustine would later declare the primacy of faith over reason.
Perhaps you have reached the same impasse with your Young Earth Creationist, who represents Jerusalem, while you are trying to represent Athens?
To give the role of evidence in creationism a more modern role, you might like to read Plantinga’s views. He said that belief in God can be argued as “properly basic” and not in need of any further justification or support from any other disciplines. You do not need what scientists regard as evidence. He has attempted to row back from this position in his later writings, as it seems to be much too permissive as to what can be basic beliefs. Why can’t we regard the “Peanuts” cartoon “The Great Pumpkin” belief as properly basic?
I am sorry if this does not seem to be the answer you might like to have in your disputation with the Young Creationist. I have tried to show that such disputations will always reach an impasse. Many people will often quote supportive evidence, interrogate conflicting evidence and therefore appear implicitly to suggest that evidence is important. However, if at some point the evidence no longer works for them, who will they do? Will they change or even abandon their position? Or will they ignore evidence?
Ask a Philosopher 
Before we accept the authority of a holy book such as the Bible on enormous questions such as the creation of everything it first has to be demonstrated that Bible is qualified to answer such questions.
The very same test applies to human reason.
When both parties to the debate fail to demonstrate the qualifications of their chosen authority, the entire debate collapses in on itself, leaving us with nothing.
It might be interesting that the overwhelming vast majority of reality appears to also be something that we commonly describe as nothing. So if we are seeking an answer which is aligned with what we can observe of reality, nothing might be a pretty good result for such an inquiry to reach.