It is safe to assume that most people are not born Atheists.*
While it is a truism that people are born without religion, one can only really claim that people are born Agnostics. Many of us would have said at some point that we believed in God, but how did we all get there? How did we go from religiosity to atheism? What about our thinking was the same? And how do we apply these principles to the rest of our lives?
When you were born, you were as undecided about religion as you were undecided about everything else, with the exception of your necessities. You knew at the time you liked getting milk over going hungry, and liked warmth over cold. Beyond that, you were pretty much undecided on the rest of the world. Your parents were your only 'gods' inasmuch as you were completely dependent on them for your survival. And upon reflection, they loved you and cared about you, so they were actually better than any god.
Once you left infancy and proceeded into childhood, you began to think abstractly. With abstract thought came the questions.
You are an atheist because you have a thirst for knowledge. You are hungry for truth. You ask questions. You will not be happy with a simple answer. Most importantly, you HATE being told "don't worry about it" in response to your questions. This mentality creates a method of dealing with information that is extremely helpful in every aspect of your life.
Atheists are the a small but quickly growing minority in the world. Since atheists are generally younger and from wealthier homes (i.e. - those that don't have 15 kids because they "don't believe" in birth control), one must assume that most atheists are "first generation". Most atheists in the west, especially in the U.S., were raised with religion. But our shift in thinking occurred for basically the same reasons.
Firstly, beware of any instance where someone tries to stop you from getting information. While many atheists deride theists for the practicality of their beliefs, we can agree that, in the majority of cases, theists are theists because they are misinformed. I really do think that if I were locked in a room for long enough with almost any theist and a computer, I could eventually convince them to at least begin questioning their beliefs.
Similarly, beware of any instance where someone tries to do your thinking for you. If someone shows you a convincing video, find the unedited one. If a politician cites a research study, look it up.
Stories about campaigns of disinformation carried out by churches are all too common these days, as the internet gives people the world's knowledge at their fingertips. Just as the invention of the printing press undid the stranglehold of the catholic church on Europe, the internet will eventually undo all religion. Back then, the strategy of religion was to prevent people from getting information. Today, the information is too available for that to work. The 21st century strategy is updated, but fundamentally the same. In today's world, religion depends on creating enough disinformation to drown out the truth. If you don't believe me, go to the Creation Museum.
Remember Shirley Sherrod? She was Obama's secretary of agriculture, and she was fired a few months ago after a video of her surfaced giving a speech that sounded like she was enacting racist policies to help African-Americans in the powerful Department of Agriculture. Admittedly, I know nothing of her policies, but that's not why she got fired. She got fired as a result of less than one minute of edited video. The unedited video of course was completely different. Shirley's story actually gave way to a very insightful speech about NOT harboring biases.
In the political arena, this strategy rears its ugly head daily. Winston Churchill once said that there are three kinds of lies: lies, damned lies, and statistics. Statistics are the tool for politicians to provide their misinformation. It is disheartening to see people using our stronghold - science - against us. People respect science because at first glance it sounds like its can't be an opinion. But when two politicians say that the same thing is going to have two different effects and cite statistics to convince you, at least one of those people is wrong.
What do these things have in common? They rely on you taking them at their word; they rely on your lack of diligence. These are two things you would never do in a debate against a theist, and should not be done while anyone tries to convince you of anything.
Finally, if you hear a message, know who is paying for it. Religions rely on patrons for their own existence. While many theists really believe that they are spreading religion for the people they are giving it to, there is always an element of self interest present anytime a church looks for new members.
Outside of religion, things generally go the same way. Ever seen those ads on TV about how corn syrup really isn't bad for you, even though it is*? Well not-shockingly those are put on TV by the all powerful corn lobby. Of course, this doesn't mean that the things they are saying are necessarily lies, but it does mean that their claims require a little more investigation. Other times, this scheme isn't as obvious. As Chris Tucker said in Rush Hour 2, "Always follow the money. At the end there's always a rich, fat, white guy waiting to take his cut."
Hopefully you can apply these principles to a grander scheme of rigorous thought. Please Comment.
*Sidenote: look to the right side of the screen right now, the second whole picture up from the bottom in the left column of pictures. Is that angelina from "Jersey Shore"? How did we miss that? In her words: "UMMMM HELLO?"
**How hypocritical would I be if I didn't include this link to a study to prove it?- http://www.princeton.edu/main/news/archive/S26/91/22K07/