The following is adapted (a little light editing; see the link for the original article) from The Theist's Guide to Converting Atheists - Daylight Atheism
I’ve assembled below a list of everything I can think of that I would accept as proof that a given religion is true. Also included are things that I would accept as circumstantial evidence of a particular religion’s truth and things that would not be acceptable to me as proof of anything.
The first category deals with things that would absolutely convince me of the truth of a particular religion. If shown any of these, I would convert on the spot.
Verified, specific prophecies that couldn’t have been contrived.
No points for trivial, vague, contrived or self-fulfilling prophecies.
Scientific knowledge in holy books that wasn’t available at the time.
If the Bible (or any other religious text) contained some piece of knowledge that the people of the time couldn’t possibly have known but that is now known to be true, that would be highly convincing to me.
Miraculous occurrences, especially if brought about through prayer.
It wouldn’t have to be so dramatic; even minor but objectively verifiable miracles would do, especially if they could be invoked by prayer.
Any direct manifestation of the divine.
I’m not that hard to convert; I’ll be happy to believe in God if he tells me to in person
The second category deals with things that would not be conclusive, but that would count as circumstantial evidence. Show me one of these and I might not convert right away, but your religion will look a lot better to me.
A genuinely flawless and consistent holy book.
True inerrancy is, so to speak, the holy grail of theism. Almost every religion claims their scripture is perfect, but none that I know of have actually met this exacting standard
A religion without internal disputes or factions.
It seems reasonable to expect that, if there existed a god that was interested in revealing itself to humanity and desired that we follow its commands, that god would write down whatever instructions it had to give us in a way that was only amenable to one interpretation.
A religion whose followers have never committed or taken part in atrocities.
If a given religion’s sacred text consistently promotes peace, compassion and nonviolence, and if that religion’s history reflects that fact, that religion would look much more attractive to me.
A religion that had a consistent record of winning its jihads and holy wars.
Strangely, none do. One can only wonder why.
The final category deals with things that would not convince me; none of the following would persuade me to rethink my position. To date, all the evidence I have ever seen presented for any religion falls into this category.
Speaking in tongues or other pseudo-miracles.
To convince me, a miracle would have to be genuine, verifiable, and represent a real and inexplicable divergence from the ordinary. Anything that can be explained by peer pressure, the power of suggestion or the placebo effect does not count. Favorable coincidences or kind or courageous acts performed by human beings also do not meet this standard.
People’s conversion stories.
I’m not interested in the testimonials of people who converted to a religion, not even if they used to be atheists. Everyone has moments of weakness in which emotion overrides logic. Instead of telling me how fast a religion is growing, how much of a difference it’s made in people’s lives, or how devoted its converts are, let those converts explain what logic and evidence persuaded them to join in the first place. If they can’t do this, their stories will not affect me.
Any subjective experience.
Saying “I know God exists because I can feel him in my heart” or something similar will not affect me. Most arguments of this sort rest on the assumption that a person cannot have a completely convincing subjective experience and be mistaken regarding its cause, but a look at the diversity of world religions easily disproves this. Christians, Jews, Muslims, Hindus, Buddhists – members of all faiths claim to have had convincing subjective experiences of the truth of that faith. Obviously, they cannot all be right. Why should an atheist accept any one of these testimonies as more valid than any other?
The Bible Code or similar numerological feats.
Creationism of any sort.
I’ve assembled below a list of everything I can think of that I would accept as proof that a given religion is true. Also included are things that I would accept as circumstantial evidence of a particular religion’s truth and things that would not be acceptable to me as proof of anything.
The first category deals with things that would absolutely convince me of the truth of a particular religion. If shown any of these, I would convert on the spot.
Verified, specific prophecies that couldn’t have been contrived.
No points for trivial, vague, contrived or self-fulfilling prophecies.
Scientific knowledge in holy books that wasn’t available at the time.
If the Bible (or any other religious text) contained some piece of knowledge that the people of the time couldn’t possibly have known but that is now known to be true, that would be highly convincing to me.
Miraculous occurrences, especially if brought about through prayer.
It wouldn’t have to be so dramatic; even minor but objectively verifiable miracles would do, especially if they could be invoked by prayer.
Any direct manifestation of the divine.
I’m not that hard to convert; I’ll be happy to believe in God if he tells me to in person
The second category deals with things that would not be conclusive, but that would count as circumstantial evidence. Show me one of these and I might not convert right away, but your religion will look a lot better to me.
A genuinely flawless and consistent holy book.
True inerrancy is, so to speak, the holy grail of theism. Almost every religion claims their scripture is perfect, but none that I know of have actually met this exacting standard
A religion without internal disputes or factions.
It seems reasonable to expect that, if there existed a god that was interested in revealing itself to humanity and desired that we follow its commands, that god would write down whatever instructions it had to give us in a way that was only amenable to one interpretation.
A religion whose followers have never committed or taken part in atrocities.
If a given religion’s sacred text consistently promotes peace, compassion and nonviolence, and if that religion’s history reflects that fact, that religion would look much more attractive to me.
A religion that had a consistent record of winning its jihads and holy wars.
Strangely, none do. One can only wonder why.
The final category deals with things that would not convince me; none of the following would persuade me to rethink my position. To date, all the evidence I have ever seen presented for any religion falls into this category.
Speaking in tongues or other pseudo-miracles.
To convince me, a miracle would have to be genuine, verifiable, and represent a real and inexplicable divergence from the ordinary. Anything that can be explained by peer pressure, the power of suggestion or the placebo effect does not count. Favorable coincidences or kind or courageous acts performed by human beings also do not meet this standard.
People’s conversion stories.
I’m not interested in the testimonials of people who converted to a religion, not even if they used to be atheists. Everyone has moments of weakness in which emotion overrides logic. Instead of telling me how fast a religion is growing, how much of a difference it’s made in people’s lives, or how devoted its converts are, let those converts explain what logic and evidence persuaded them to join in the first place. If they can’t do this, their stories will not affect me.
Any subjective experience.
Saying “I know God exists because I can feel him in my heart” or something similar will not affect me. Most arguments of this sort rest on the assumption that a person cannot have a completely convincing subjective experience and be mistaken regarding its cause, but a look at the diversity of world religions easily disproves this. Christians, Jews, Muslims, Hindus, Buddhists – members of all faiths claim to have had convincing subjective experiences of the truth of that faith. Obviously, they cannot all be right. Why should an atheist accept any one of these testimonies as more valid than any other?
The Bible Code or similar numerological feats.
Creationism of any sort.