My deconversion was due to skepticism about the supernatural in general, and due to learning about other cultures in Anthropology courses in college and by meeting people of other backgrounds as an adult. Science to me was the antithesis of pseudo-science, not of religion... at least while I was still going to church trying to "connect" with the religion of my childhood.
The skeptical literature I read at the time concerned things like:
- the numerical impossibility of souls being reincarnated
- fake faith healers' "miracles" no more than magic tricks
- "chi" of Eastern pseudo-medicine has no basis in fact
- psychics use "cold reading" to fool people
...then I went trippingly through life free from the burden of wondering whether I'd go to Hell or whether some supernatural judge was eavesdropping on my thoughts. I let people know I was an atheist, but unless they were part of a batshit crazy denomination or tried to convert me, I didn't press the issue. (Heh heh, do NOT send me Godspam! You've been warned!)
...and then I discovered atheist stuff on the interwebs. ...and then the "New Atheist" movement created a few books for me to stumble across at Borders Books (*sniff* still miss the place)
If you are new to atheism, you'll notice that the "professional atheists" tend to come from a few scholarly disciplines. Only Christopher Hitchens could be counted as a "regular guy" who just told it like it is, though he was a professional journalist so only semi-regular. Here are the disciplines some bullies think you have to be conversant in to have an opinion:
- Ancient History
- Evolutionary Biology
...and possibly a few others. Fortunately, you don't really have to be conversant in a bullshitter's favorite form of bullshit to call them on their bullshit. But it helps. For the most part, though, we encounter believers who ask the same rather inane questions of us. Sometimes there are some sciency answers to the questions they ask, because they think their religion explains sciency things.
Here are some "answers" for newbies:
When you die, your brain cells stop doing what they do and you stop being who you are. It's hard to accept but "we" are our brains. Just ask someone who's been shot in the head and survived. Oh wait, ask their family for a better answer.
Near-death experiences just prove that the brain has a process during death, not that there is a bright light in another plane of existence.
Where we came from is a series of totally natural processes that took millions of years. That includes possible abiogenesis (life from nothing) from chemical building blocks of what are now cells. It includes evolution, which the process of advantageous variations giving a few individuals an edge, while most variations are neutral. You don't have to know every detail of all these things to know that "God did it" is a cheap and superficial answer.
Why are we here? We just are. If you need a reason for your existence, find one for yourself. Nobody gave it to you. That's okay, because the people who find a "reason" in their religion have really found it for themselves, too. They all find different purposes even when they supposedly believe the same things.
Yes, most of the stuff of religion is factually wrong. Sometimes it's accidentally wrong, and sometimes it's intentionally wrong. Just because some historical details from the Old Testament are true doesn't make the supernatural details from the Old Testament True. Atlanta really burned during the Civil War, but that doesn't make Gone with the Wind a true story.
There is wonder and mystery and poetry in the Natural World. You don't need to add a supernatural dimension to find that. It's there if you look.
Your brain is a fabulous thing, but it can deceive you. Under certain conditions you can see or sense other beings, feel a warm comforting feeling, or give yourself the will to continue under stress. Much of that you can get from relationships with other people. Cultivate your relationships and you'll find you haven't lost much by disbelieving in the supernatural.
Knowing the classic fallacies helps to see through nonsense when it's presented to you. "False prophets" are everywhere, but now you can call them what they really are: charlatans.
Trust in the scientific method and the people who use it is not the same as faith in a supernatural deity. If the scientific method didn't work, it would be thrown out because scientists care about what's true. Believers will cling to what is demonstrably false..
...well, for awhile they do. Welcome to the World of What's True, newbie!