I was. There is a reason we don't have words for people who believe or do not believe in Russell's teapot as well as a host of other such examples. There's a reason that atheism has the ending it does - ism. We can certainly assert that atheism is merely lacking a belief in god such that rocks, babies, people who don't speak English and don't know the word "god", etc., are all automatically atheist but I have found that most of the time those who do such things seem to have ulterior motives.
My motive is clarity of language. I've found that the definitions of "atheist" that exclude babies tend to be either transparently arbitrary or logically unviable... and don't actually reflect how the word is used.
And I've found that most of the time, ulterior motives work in the other direction: it seems to me that when people object to the term "atheist". It's as if their mental image of "atheist" is Richard Dawkins (or Madalyn Murray O'Hair for the old school), and they think something like "he's nasty and evil but babies are sweet and innocent. Something as good as a baby can't be something as bad as an atheist."
And agnosticism, especially the way Huxley defined it, would be beyond the capability of a baby, since it's (in Huxley's formulation) an APPROACH to claims akin to skepticism or (in most modern usage) a positive claim that the question of God is unanswerable.
Hence the ludicrous proposition that without a clear definition of god one can't even assert that one doesn't believe in god or the not quite as bad claim that disbelief and a lack of belief are somehow equivalent.
You don't need to have a clear definition of "god" if you define atheism in terms of lack of belief. Generally, if I can't even conceive of a thing, then I can be sure that I haven't accepted that the thing is grounded in reality.
However, if you define atheism in terms of rejection of belief, and if you require someone to reject all gods to be an atheist (which we need to do if we want to avoid the absurd case where a person is simultaneously a theist and an atheist), then we do need a clear picture of exactly what needs to be rejected.
Huxley coined agnostic for a reason: there wasn't an adequate term to define someone who didn't know whether god exists (and therefore can't be said to believe in god) but who didn't disbelieve either. Of course, there's no reason his definition must hold now (language doesn't work like that), but too often in discussions such as these all terms become meaningless in an attempt to dogmatically defend what appears to be some odd philosophical objection to having theists gain "the upper hand" in some way.
It's not an objection to theists having the upper hand; it's an appeal to rationality in language. A definition like "an atheist is a person who is not a theist" is perfectly straightforward and, IMO, matches how people use the term.
OTOH, I've yet to see a definition using rejection of belief that matches how people actually use the term "atheist". The extreme effort that I've seen people go to in order to come up with contrived definitions makes me think that something else is going on: atheists are "bad", babies are "good", so they reject applying a perfectly appropriate label based on emotional baggage they've attached to the terms.
When someone denies that there is a god, or believes that there is no god, or disbelieves in any god, then they can be said to be an atheist. I prefer to be more inclusive and say atheists also reject other spiritual notions but I would certainly not try to tell someone who believes in e.g., souls that they can't be an atheist. The primary, central definition is right in the word and it doesn't refer to souls, the afterlife, or other religious notions but to god. It has the suffix it does because it is a doctrine or a system of belief (it informs a worldview).
It also has an "a" prefix. Just in terms of the structure of the word, it would work just as well to interpret "atheism" as "NOT the belief system of god(s)" as it would "the belief system of 'not god(s)'."
It exists as a word because even today theistic worldviews shape our understanding, culture, concepts, language, politics, etc. It would make no sense in a region where there was no concept of god. It loses all meaning to equate it with an infinity of words that could exist if we wished to all waste time thinking of other things that exist at least in thought or which are made up on the spot and added -ist or -ism to make up words to define the denial of these entities.
To be an atheist is to make a statement of belief: "I do not believe in God (or gods)." We make the word meaningless by trying to pretend that babies are atheists because they don't have a belief about god. It's one thing to ask whether children (not babies) are inclined towards theology if exposed to it and will tend to invent at least some proto-theology or some spirituality, but it makes as much sense to ask if babies are atheists as it does to ask if they're communist or Buddhist or a creationist.
Are babies not also non-smokers? Non-swimmers? Apolitical? A person doesn't have to reason his way into a label for it to apply, and this fact doesn't render the label meaningless.
