Atheists don’t believe in any gods. Claiming that everyone is absolutely an atheist doesn’t make much sense. If someone says he believes in the god of the Western religions, we’ve got to take his word for it. That is, at least, if we want to be totally practical.
No such thing as an atheist
To deny people’s religiosity is dodgy, akin to the common attempts of religious apologists to claim that there’s no such thing as an atheist, that atheism is a religion, or that atheists are only calling themselves such because they’re “angry at god.” These are examples of excuses for outright denial and are inaccurate.
However, in certain contexts, one might be able to argue that everyone is an atheist – in a far-reaching philosophical sense, rather than a really practical one. Atheists often make the claim that an all-loving (omnibenevolent), all-powerful (omnipotent), all-knowing (omniscient) god is a logically impossible god, considering the world we live in. How could such a god allow evil to exist? This problem is known as the “problem of evil.”
Could this all-powerful god create a stone so heavy that he could not lift it?
Another commonly-known logical problem with the idea of such a god is the question: “Could this all-powerful god create a stone so heavy that he could not lift it?” No matter the answer, the god in question can not be all-powerful and must be all-powerful, at the same time. This translates to a logical impossibility, a paradox.
A logically impossible thing can not exist, and further, if understanding is considered to be a representation of reality held in the mind, a logically impossible thing can not be fully understood.
The next question is: if a concept or thing can not be understood, can the mind believe in it? Or does the mind just THINK it believes in something that is, by definition, can not? If the latter is true, all “believers” are actually just confused, atheists. They think they believe, but can’t, because you can’t ‘really’ believe in something you can’t understand.
This argument is playful and open to discussion and should be taken with a grain of salt. In all practical respects, it doesn’t apply.
The statement that all monotheists (believers in One True God) are atheists can work in one additional context: relative to other gods. The atheistic biologist Richard Dawkins brings this up often in debate. A Christian might ask him, ‘What if you’re wrong?’
He’ll respond, ‘What if YOU’RE wrong? About Thor, Zeus, and a multitude of other gods just as likely to exist as the Judeo-Christian one?’
Theists are atheists about some god or other
All theists are atheists about some god or other: that’s the main argument. It’s true in a way – all Christians disbelieve in certain other cultures’ gods – but that makes them atheists only in a relative way, rather than an absolute way, since usually, “Atheism” refers to not believing in any gods at all, period.
Dawkins’ point in calling religious people (like Christians) atheists is to show that they disbelieve in other gods for the same reasons, and in the same ways, that total atheists disbelieve in the Christian god.
Historically, it’s common for the religious to call people of other religions ‘atheists,’ even if everyone involved is technically theistic. For example, the Romans called the Christians atheists when Christianity was forming, simply because the Christians didn’t conform to popular Roman notions of gods. The use of the term ‘atheism’ can change contextually, once in a while.
Everyone’s a relative atheist, but absolute atheists are far less common. Saying “everyone is an atheist” is an attempt to bridge the gap between total (atheistic) and partial (monotheistic) non-believers.
The message to theists is this: if you don’t believe in the thousands of other gods created by human folklore throughout history, why not just go “one god further?”