Though the number of nonbelievers in this country is on the rise, many people are still unclear as to what "atheism" truly means. Recently, I've encountered individuals on a wide variety of sites who insist they "know" certain things about atheists, from our supposed megalomania to our penchant for being brutal dictators. These assertions are often wildly inaccurate. Here are a few things to remember about the freethinkers in your life.
In fact, atheism is the result of a philosophy. It describes the view that there is simply no evidence for supernatural forces, imaginary friends, gods, or otherwise. Skepticism is the tool, atheism is the consequence. Atheists are not motivated by atheism, they are motivated by a dedication to reason. Thus, the argument "But X,Y, and Z terrible dictators were atheists, therefore atheists are evil!" misses the core idea: Atheism tells no one to do anything. Unlike religious texts, which describe methods of worship (keep the Sabbath, mutilate your genitals, spread your beliefs with a sword, etc.), skepticism gives no normative instruction.
Sam Harris sums it up quite beautifully:
“Atheism is not a philosophy; it is not even a view of the world; it is simply an admission of the obvious. In fact, 'atheism' is a term that should not even exist. No one needs to identify himself as a 'non-astrologer' or a 'non-alchemist.' We do not have words for people who doubt that Elvis is still alive or that aliens have traversed the galaxy only to molest ranchers and cattle. Atheism is nothing more than the noises reasonable people make in the presence of unjustified religious beliefs.”
Atheists are frequently derided as amoral, presumably because many assume humans are incapable of being good without god. Recently, the Catholic Church made sure to remind atheists that we'll all wind up in hell. (As you can see from the picture below, at least we'll be in good company.) However, to most atheists, morality exists outside of — and indeed predates — religion. This means we believe humans to be fundamentally capable of conscientious, ethical behavior without an oppressive authority or fear of eternal torment to keep us in line.
This belief in the fundamental capability of humans to live good lives leads many atheists to humanism. Humanist groups like the American Humanist Association emphasize our capability and responsibility to work to improve the human condition, realizing two hands working can do more than a thousand clasped in prayer.
If Cthulhu, Mohammed, or Thor show up tomorrow, atheistic ideas will be subject to revision and evaluation, just like any other rationally-derived conclusion. Atheists, as skeptics, will challenge and update their theories as their body of knowledge grows. This willingness to revisit accepted theory is a fundamental aspect of science.
Historically, the heliocentric model deposed the geocentric model, phlogiston theory was replaced by oxidation, and the caloric was replaced by the mechanical theory of heat. The distinction cannot be emphasized enough: Science corrects itself when it is wrong, and gains explanatory power in the process. Scripture, on the other hand, remains static, as its authority draws in part from its immutability.
When skeptics point out the flaws in religious creation stories, we are often met with the response that we have no better explanation. But this is a fundamentally flawed argument. Atheism doesn't require that you have alternate explanations to existing religious beliefs.
You don't have to be sure about the Big Bang, the origin of life, or the existence of intelligent aliens to reject the idea of a seven-day creation story, reanimation of the dead, or talking snakes. Quite simply, the lack of an alternative explanation does not make the religious explanation any more likely.
The certainty of many religions answers to life's greatest questions is what can makes religion so psychologically appealing. Our brains are wired to crave certainty. Thus there is a real biological cause for the fact that we are more comfortable when we are sure about a given subject. It may be less cognitively pleasing to maintain a position of indecision, but an honest assessment of the situation is preferable to the fantastical guesses of world religions.
This one is an important distinction to make, as the two terms are often incorrectly used to describe opposing sides of the same coin. Gnosticism, from the Greek word gnosis, meaning knowledge, is used to indicate absolute certainty in a specific belief. Thus, "a-gnosis" describes degrees of uncertainty about a specific belief. Theism, as noted above, is commonly described as a belief in god. Hence, "a-theism" is its opposite.
Gnostic theists, therefore, are absolutely sure that god exists. Conversely, an agnostic atheist is convinced there is no god, but doesn't rule out the slim possibility he could be wrong, much as one might not totally rule out the existence of unicorns. Thus, many atheists you meet are also agnostic, and many theists are as well. Richard Dawkins, perhaps the world's most prominent atheist, describes himself as an agnostic atheist. This means he sees a very low probability of god's existence, but short of zero. In his book The God Delusion, Dawkins explains it clearly: "I don't know for certain but I think God is very improbable, and I live my life on the assumption that he is not there."
This is atheism's defining feature, and it often gets lost in the debate. Atheism isn't about egotism, megalomania, or persecution of believers (we've been on the receiving end too long, and know how it feels). Neither is atheism about Jesus, the Flying Spaghetti Monster, or Vishnu. Skepticism is about setting a standard of proof to be met before we accept assertions as facts. Just as we demand evidence before we accept phenomena like climate change, we ask for proof before we bow down before alleged supernatural forces.