The term “non-theist” already exists to denote individuals who merely lack belief in God.1 This is relevant because re-defining atheism to refer to a “lack of belief” would both make the term superfluous and, in addition to introducing mass academic confusion, would rudely inconvenience real atheists. After all, whereas they had always been able to simply say “I'm an atheist” in the past, every atheist would now always be required to say or write-out “positive atheism” and say “I'm a positive atheist” (which just seems awkward and unnecessarily burdensome given how frequently the term is used in some disciplines).2 Moreover, it seems clearly more appropriate to call babies, cats etc. non-theists, rather than atheists.3
In academic settings (peer review etc.), atheism is consistently understood as the belief that God does not exist. For example, in specifically contrasting it with the “lack of belief,”
• The Cambridge Dictionary of Philosophy: “[Atheism] denotes a belief that there is no God; this use has become the standard one.”
Few dictionaries of philosophy even go so far as mention the non-standard “lack of belief” use, despite wide-spread use on the internet (especially YouTube). This is presumably for the same reason most biology dictionaries do not mention definitions of evolution which include the origin of the Universe or first life (widely used by Young Earth creationists, again, especially on YouTube). A few academic atheists have suggested changing the standard definition, but to no avail.1,2 Today, “The theist is commonly regarded as one who believes theism; the atheist believes atheism.”3
Theism and atheism are clearly contradictories. Yet, if they can be true or false, then they are both beliefs (or propositional stances). However, a “lack of belief” is not a belief or propositional stance; it cannot be true or false.1 So, on the revisionist model, while there can be arguments against the truth of theism, there suddenly cannot be arguments against atheism (i.e. by definitional fiat, the revisionist sets up “atheism” such that it cannot even be refuted). This seems straightforwardly odd, especially since there is a rich history of proffering arguments supporting “atheism” (by that name).
The revisionist “lack of belief” definition of atheism is overtly ambiguous. After all, there would suddenly be two ways to be an “atheist,” by either…
(a) …affirming the proposition <God does not exist>, or…
(b) …withholding belief about it (traditionally called “agnosticism”).1
This would in turn needlessly require interlocutors to spend extra time discerning which of those two remaining options apply, rather than the individual being straightforward about his position from the get-go. Right now, things are efficient: One simply says whether they are a theist, atheist, or agnostic. Simple.2
The Greek roots of “atheism” yield “not theism.”1 [See response]2
But so what if that were true? Such an argument commits the “root fallacy”; a words meaning is simply not bound up with its etymology.3
Several everyday people on the street understand “atheism” to denote a “lack of belief” in God.
But, so what if that's true? Couldn't people commonly understand a term to mean something that it does not actually mean? For example, “schizophrenia” is commonly, and yet mistakenly, understood to refer to multiple personality disorder.1