But these aren't all. Buddha attained enlightenment under a Bodhi tree. Mormonism is based on the revelations received by Joseph Smith. Where L. Ron Hubbard got his stuff is scary to contemplate, but it seems he received "revelation."
Or was this all revelation? L. Ron Hubbard sought psychiatric treatment during his 30s, long before learning the truth about aliens and humans, and then founding an anti-psychiatry "religion." For the others, psychiatric treatment wouldn't have been possible, as the field of psychiatry wasn't developed until the twentieth century. If Moses or Paul or Mohammed were alive today, would anyone take them seriously? And how is Mormonism growing when it's based on such a psychotic story?
The thing is, revelation is indistinguishable from psychotic symptoms. When Moses saw the burning bush, was there really a burning bush? Conveniently, he was alone, so if it happened at all, there is nobody to corroborate it. He could have been having alcoholic psychosis for all we now. How about Paul's revelation? He was alone as well. Joseph Smith? Who was that angel that directed him to the golden plates, that eleven people supposedly also saw. Those eight would have been subject to incredible pressure from Smith to validate his revelation. After being guided to the plates, he viewed them through a magic hat and was able to dictate a translation from ancient Egyptian. So even though he supposedly had witnesses, nobody else was privvy to the revealed wisdom except via his translation. That's convenient.
This is what http://www.schizophrenia.com/ has to say about hallucinations:
Hallucinations are false perceptions, inaccuracies that affect our senses & cause us to hear, see, taste, touch or smell what others do not. In the acute phases of schizophrenia, patients are likely to insist they are hearing voices that no one else can hear. Sometimes they hear noises, clicks or non-word sounds. On occasion they are disturbed by seeing, smelling or feeling things that others do not.
Descriptions of these perceptions differ. Sometimes they are experienced as very forceful & apparently important thoughts. Frequently they seem to come from outside the self & are heard as conversations between other people, or commands, or compliments (or insults) addressed to the person. Sometimes the voices are reassuring, at other times menacing. Often the remarks heard are not addressed to the person but seem to be concerned with them in an unclear (but perhaps derogatory) way. Individuals who experience this describe it "like a tape playing in my head". The experience is so real that many schizophrenics are convinced someone has implanted a broadcasting device in their bodies. Or they come to believe in a supernatural explanation for the strange sensation. It is so real to the person that it cannot be dismissed as imagination.
This sounds a lot like what Moses, Noah, Abraham, Joseph, Jesus, Paul, the author of Revelation, Muhammed, Buddha, Joseph Smith and L. Ron Hubbard experienced. In the modern age, people who claim to hear angels, or to be the son of god, or to just know things nobody else knows, are considered psychotic. In fact, religious delusions are rather common.
If we are to accept that one or all of the religious revelations of the major religions are actual, true, communication with a supernatural entity, then why not accept the religious delusions of the psychiatric population? A very few are lucid enough to be very convincing. The dangerous ones are called "cult leaders." The somewhat less dangerous ones have been called, or called themselves, "prophets."
What distinguishes a psychotic from a prophet? Charisma, control and a gullible audience.
I would imagine this would be a recipe for prophesy.
Should people who are aware of the symptoms of psychiatric diseases believe in anything that's based on people hearing voices, seeing burning things that nobody else sees, or believing themselves to be divine? I say, no. That is absolutely no basis for a belief system for a relatively sane person.
I stop short of calling believers delusional, because they aren't the ones with the psychotic symptoms. They are the vitims of delusional people. They have been convinced via some very clever and charismatic manipulations. I don't blame them for this but I do think they should be mindful of the fact that their psiritual heroes would be considered psychotic today.
Sadly, people with religiously-associated symptoms have caused a lot of damage, possibly more than people with other kinds of psychoses. Andrea Yates killed her children. Jim Jones killed his and others' children. People have killed themselves because of what a delusional yet charismatic cult leader told them. People have killed others because of what their cult leaders have told them.
If a person is born into a society full of people who believe in stories that would be considered psychotic today, you can't really blame them for believing their voices and believing the people who believe the voices.
But I have to ask believers: why do you consider Harold Camping or Jim Jones or Andrea Yates crazy, but not the author of Revelation, or Paul, or Abraham? Your religion isn't only based on ancient hallucinations and delusions, but it creates and atmosphere where mentally ill people feel even more justified believing their symptoms are real, and where others feel justified in following them.
I remember as a child, asking my grandmother, "Why did God stop talking to people like he talked to Noah?" She had no answer. With mental illness in our family, what could she say? Humans, there's mental illness in our family. It's time to call a spade a spade and accept that ancient delusions are not real and true revelations of anything but insanity.
2. Authority of ancient (or even modern) texts.
Of course, you give people too much credit when you assume they always intend to transmit information faithfully. Sometimes "faithfully" means putting in or taking out words or stories they think are "wrong." The translator, copyist, and publisher may believe they would get it right because they prayed before they did their work each day, but since they come up with different variants, apparently those prayers don't wor.
And then there are the intentional changes. I have reviewed two excellent books on the writing of the Bible. The Bible Unearthed uses findings in archaeology to analyze the supposedly historic stories of the Old Testament, finding that there is some truth in them but the final revision was considerably influenced by political spin. Forged by Bart Ehrman discusses the practice of outright forgery of religious texts during the early centuries of Christianity. (Some of these forgeries made it into the Bible)
"You can't believe everything you read," and that should go double for ancient texts. But "fundamentalists" believe the older the text the more authoritative it is. Well, it may be authoritative in that it represents the beliefs of people living in a certain cult at a certain time, but in no way can these ancient texts be considered "The Truth."
3. Culture / Tradition.
Most people believe in the religion that's dominant in their culture. In Shintoism. The received narrative of the religion was written down eventually, not as revelation, but as received wisdom. For other religions, it's the way received delusions transmitted via ancient texts gets played out for average people. Judaism, for example, includes "historic" texts that define the ethnic and cultural group as well as spell out the belief system.
The culture is really the more important of the two. The God Delusion makes some cogent points about this. Many of the "rules" of religions are systematically ignored, while other rules are used to prop up rules that society already likes. Morality is defined by community, and communities change over time. Slavery is the most famous example in the United States. Pro-slavery advocates drew on the Bible for justification. Abolitionists drew on the Bible as well.
And then there is the "I Love Jesus" youth movement that relies on peer pressure and pop music to keep secularized kids in the flock. (Such as Fields of Faith)
There are so many varieties of every major religion that it can't merely be due to psychotic prophets leading splinter groups. Sometimes these groups do consciously separate themselves due to their splintering, but other times they are just part of a form of cultural evolution.
Basing your life on a religion because you grew up in it makes sense; we want to belong to our society. But the fact that your parents, pastor, neighbors, or even your new friends in your goofy cult believe a certain belief does not make that belief true. This is the ad populum fallacy. High numbers of believers is an indication of the religion's effectiveness in proslytizing or of holding their members under tight control. It doesn't mean that one set of founders had more true psychosis than all the other psychotic founders.
The term "freethinker" is really the best alternative to "atheist" in my opinion. People who are bound by culture aren't free to question the basis for the culture. In some places it could get you killed. But if you look behind the authority of the people, books, and stories you have been led to believe are "true" you may change your mind. Once you have freed your mind from authority, true "seeking" begins.
You may be born into a culture with a dominant religion, or you may be born into a family that is part ofa religious minority. As a child, your family is your culture; your parents are your gods. Many children go to church from infancy, and even if they don't understand any of it, they do get that this is an extension of their family, because their family takes them there. You may then go to religious school, which is a further extension. It's all very comforting and cozy, but that doesn't make it true.
I have known many people who are children of pastors and never question whether what they learned was true. At root, they trusted the authority figures, and that the authority figures knew what was true. Their authority figures decided what they should believe; they didn't. Questioning the truth of the holy books would be the moral equivalent to questioning your parents, and conveniently, many religions teach their children never to question their parents.
The fallacy here is appeal to authority. Of course, some authorities do get things right, but the rightness of their opinions isn't dependent on their authority. You can tell how much authority means to some Christians when they bring up Darwin, or his current bulldog, Richard Dawkins. If neither of these men had ever been born, there would still be a theory of evolution and there would still be people calling bullshit on evolution deniers.
So... psychosis, written down, used to convince others to believe in the hallucinations, and then indoctrinated in children, is no basis for a belief system. It's understandable, but not in any way guaranteed to be true. Quite the opposite.