1) Since the theist is the one making the claim, the burden is on him to prove it.
2) The only acceptable proof is Scientific Evidence.
This might seem like a reasonable expectation but in fact it is an impossible one, by definition. It’s sort of like the following:
The misunderstanding here is what constitutes a fair playing field. Theists think it is perfectly fair to say that something that was revealed to them after a prayer, is valid input into the discussion. Or that “my pastor told me” constitutes a statement of authority. The problem is, even the statement “a study was done and its conclusions were…” doesn’t count as “fair”. The study itself could be flawed. Even a well done study doesn’t prove anything, it is just more evidence in the spectrum of finding the truth.
But it isn’t necessary to understand the details of how scientific evidence is evaluated or how science has improved its self-correcting mechanisms over the last 100 years. All you need to do is look at the commonly known history of the Western world. In that history, the Greeks started figuring out the size of the earth and how the planets moved and how to treat the sick. Rome then collapsed under the weight of its own politics. The books written by Ptolemy and Galen continued to be used in European Universities for 1,000 years with very little improvement. Just about any malady might be treated by letting out some blood or trying to balance your humors. None of it was effective.
Advances in technology were made very slowly because if you experimented with an idea or questioned something that the priests said, you could get branded as a heretic or a witch. These offenses sometimes carried the death penalty. Under that system, a system analogous to the all boy’s basketball competition, science managed to get a foothold and eventually won.
Under that old system, when Christianity lost a competition, as when they lost Jerusalem to the Muslims, they played by their rules. They returned to Jerusalem with a bigger army and slaughtered the Muslim citizens and took it back. This could have gone on for centuries if it weren’t for the people who started looking for a better way. Of course conflict still does go on, but with a lot less slaughtering. I make no claims that science has solved all of the problems of the world, or that it won’t be replaced by a better system in the future.
Once science showed that it could compete, that it could answer questions that religion could not, that there were ways to settle a dispute without threats of violence to your opponent, they also changed the rules of the competition. Instead of continuing with a system that allowed whoever won to set the rules, they started working on a system that is fair. They said you could use something that was written 1,000 years ago to show your idea was correct, but you could also question it. If you say you have a cure for something, then you simply need to demonstrate that it works. Saying that it works because it has always been done that way was no longer acceptable.
Some ideas are complicated. The results are not immediate. Demonstrating them is not so simple. Evaluating them requires experience with similar ideas. The system of reviewing evidence and getting funding to even create the evidence is complicated. It’s difficult to evaluate the system of how we evaluate things, let alone evaluating the thing itself. But we are comparing this to the old system where you needed the approval of a hierarchy of men who elected each other and promoted each other based on their approval of each other and their adherence to the ideas of those who approved and promoted them. There may be flaws in the current system but it is a system where you can demonstrate why you think your idea is true, using reason and evidence. That is what I consider fair.
There are professors, there are scientific journals, there are hoops to jump through and requirements to be met, but there are no more witch burnings. There is corruption, there are cliques and networks, but there are review boards and competing networks that work to break up those log jams and clean up the problems. When I hear of people complaining about their scientific papers not getting published or their ideas not being listened to, I almost always find out it is the merits of the idea that are lacking, not the merits of the methods that are evaluating those ideas.
I can’t know everything. If I were alive in the 13th century, I might have noticed that blood letting was not very affective, and the herbal medicines of a woman living in the forest were, but today, I’m not able to evaluate all the current potential cures for cancer. If were ever to get cancer, I would have to rely on others to help me decide on my treatments. At some point, you have to decide who to trust. For now, I’m going with the people who are certified by a system that uses evidence, not the non-witch burning people.