Do children start out atheist?

Tautology in reference to a baby. Babies cannot accept or not accept any preposition.

The religious leanings of the authors are immaterial. I've shown that babies do NOT qualify under of the definition YOU offered. Your definition required atheists to have had NOT accepted as true (believe) the existence of a god or gods. Babies have NOT done that. Babies are not atheists because they have not NOT accepted as true (believe) the existence of a god or gods, a requirements of being an atheist by your definition.

Infants are specific human beings.

This makes them people.

They don't have belief in the existence of a god or gods

...being both people and not believing in the existence of a god or gods makes Infants atheists.

Which of the following do you assert is false? 

Infants do not believe in the existence of a god or gods. 

Infants are people. 

You keep skirting that directly relevant question. Do you agree with those statements? 

So what? Infants have not rejected belief in god.

Tautology. They have no belief in anything and cannot have beliefs in anything. Saying of a baby, "It doesn't have belief in the existence of a god or gods  is silliness when a baby cannot have belief in the existence of a god or gods.

No sir. Being people and rejecting a belief in the existence of a god or gods, makes people atheists. No one is atheist simply because they exist.

Of course not. One is illogical and the other is irrelevant.

An atheist isn't necessarily someone who has rejected belief in god. An atheist is simply a person who disbelieves or lacks belief in the existence of a god or gods. 

Rejection is not required for that definition to apply...

Infants are people.

The statement that infants lack belief in the existence of a god or gods is meaningful to this discussion.

It directly Impacts if they meet the criteria necessary to be an atheist.

This leaves us to determine if they disbelieve or lack belief in the existence of a god or gods.

Their lack of belief in the existence in a god or gods is what makes them atheists.

...it is the only conclusion that makes sense given the above definition of atheist.

Then the White House is an atheist. You can't have your cake and eat it too. Your own  definition specifies the rejection as a condition.

Then trees and platypuses do too. Your definition said rejection of a belief in God or gods was a criteria. A rejection requires knowledge of. Babies do not meet the criteria

Then flat head screwdrivers are atheists too!

Now you say, flat head screwdrivers aren't people. So, tell us, why is people-hood is a criteria? Because only people think. But babies don't think! It is not being people Alone that makes one an atheist, it is being people + rejecting belief in God.

if you say babies are atheists, then it must be only their people-hood causing them to be atheist, for they have rejected nothing! That is on its face illogical.

If you think the only criteria is not having a belief in god, then frisbees are atheists, for your criteria of people-hood must be coherant. In other words, why must an atheist be a people? Do you have an answer?

No atheist sees a baby and thinks "ANOTHER MEMBER OF OUR CABAL IS BORN! HAIL YE PHYSICS AND SCIENCE!"

Now you say, flat head screwdrivers aren't people. So, tell us, why is people-hood is a criteria? Because only people think. But babies don't think! It is not being people Alone that makes one an atheist, it is being people + rejecting belief in God.

if you say babies are atheists, then it must be only their people-hood causing them to be atheist, for they have rejected nothing! That is on its face illogical.

Sorry, it simply doesn't make sense. There is a reason atheists have been restricted to people. That reason is not true for babies. Babies are people, but do not qualify under the definition.

Your only 2 logical choices are to,

1. Ditch the peoplehood/thinking requirement, rendering all inanimate objects as qualifying as atheists, or...

2. Keep the peoplehood/thinking requirement, rendering all infants as unqualified under the definition.

Point one is a strawman there is no people/thinking requirement, 

simply a people requirement. Infants fit that. They are people, they fit the first criteria to be an atheist.

Point two is also flawed in assuming person = thinking.

I consider infants people. They fit perfectly under the definition.

Can you support the claim as to the reason atheist requiring thinking to be part of the definition?

Now you say, flat head screwdrivers aren't people. So, tell us, why is people-hood is a criteria? Because only people think. But babies don't think! It is not being people Alone that makes one an atheist, it is being people + rejecting belief in God.

if you say babies are atheists, then it must be only their people-hood causing them to be atheist, for they have rejected nothing! That is on its face illogical.

If you think the only criteria is not having a belief in god, then frisbees are atheists, for your criteria of people-hood must be coherent. In other words, why must an atheist be a people? Do you have an answer?

Untrue. The "people" requirement is due to the fact that only people think. If you remove the thinking requirement, you lose the logical reason for restricting the definition to people.

1. Why is personhood necessary for atheism? Why can't a scarf be an atheist?

2. What is it that makes a lemon tree different from a person, and thus, unqualified as an atheist?

Disbelief and (or) lack of belief are being used synonymously, because it is specific to the existence of God or gods. Atheism isn't defined as "lack of beliefs" it is specific to the rejection (or disbelief) in God (or more specific, to the existence of God), as opposed to Theism. The definition would not exist without the cognition and understanding of theism, thus an understanding of God is necessary. This is so simple to understand, I have a "lack of" patience engaging any further in the topic at hand.

Lets call a disbelief in leprechauns A-gnomism.....as opposed to gnomism which is a belief in leprechauns.....Saying I lack belief in leprechauns is also saying I disbelieve in them, or have no belief why? because I first have cognition of them to have no belief specific to the existence of leprechauns. Claiming I lack beliefs is not the same, it has no relevance to A-gnomism specifically.

A-gnomism is not a lack of beliefs, that's not how it is defined, it is a disbelief (or lack of belief) in leprechauns. Again, the misconception that atheism means a lack of beliefs is somewhat silly, because we all know that without the cognition of Theism the term makes zero sense, it no longer means anything not to mention the reality that the definition itself insists the cognition of the existence of God or gods. There is no word for "lack of beliefs", other than saying "lack of belief". Babies can lack beliefs, but can't disbelieve in God (which is synonymous with a "lack of belief" IN GOD). .

A-theism was intended as a term for the lack of belief (or disbelief) in God specifically, for one to have no beliefs in the existence of God specifically one has to be aware of such concept otherwise a-theism is a worthless term. Without a belief in God there can be no term opposing it, and upon opposing it or rejecting it the term a-theism now has relevance. A baby cannot be an atheist (which is an opposing position to the existence of God or gods), though they can lack beliefs.

This is your repeated assertion, it is however unfounded.

I have addressed this, it addresses humanity.

It addresses the fact that humans are the only beings we know of relevant to the discussion of religion.

I haven't dodged any question, I've already answered this question. It's because of humanity, of all known species humans are relevant in the discussion of belief in a god.

Because only humans are relevant.

Because only humans are relevant.

Because only humans are relevant.

It's because of humanity, of all known species humans are relevant in the discussion of belief in a god.

I won't dismiss babies from the position of being human.

Nor will I accept the effort of theists to shoehorn in 'rejection' into atheism/atheist.

There is no implication or necessity or rejection or knowledge of god in the definition of atheist, only that one is human and doesn't believe in god. 

Let's just say for the sake of argument, there were common ancestors. With which common ancestor would the superstition, and God concept begin with?

I don't know and it's immaterial. If we assume common ancestors, then we can logically conclude that at some point one of them had the concept of god for the first time. If you want to assert that can only have been so if it was given to them by god, then I ask can you show that this is the case? If it could have formed without revelation from a god, then why is it unreasonable to consider that a possibility?

The only concern in the animal kingdom is food, sex, and sleep. Some animal infants are lucky if their parents nurture them instead of eat them.

So logically the further we would go back in the alleged evolutionary chain, the less likely of any concern outside of basic needs and pleasure.

This is again immaterial. Would you agree that humans are capable of having ideas? Would you say it's possible for humans to create complex fictions? If so, then why couldn't a humanity entirely devoid of the concept of gods imagined their way to that concept on their own? What relevance does our ability or inability to pin point when we became capable of conceiving of god have to do with the question of if babies are atheists?

Do claim babies believe in a god?

Do you accept babies are people? 

Sure, but that's your opinion. We know that people can imagine. We know that we can come up with ideas that are either true or false (intentionally or otherwise) and that people can believe ideas, regardless of if they are true or not.

Why is it so implausible a position to consider that early humans anthropomorphised the world around them? We anthroporphise a great deal after all.

As for why they'd take the time, the world was scary and dangerous and brutal. Don't you think the idea that intelligence and powerful beings that bring good and bad events into our lives wouldn't have been more comforting than the idea that disasters were simply beyond their control? At least with a being doing it we can hope to bargain or at least find reason to the events.

It's not so much that's it's an impossibility, but it's a huge stretch.

Sure, some assumed male common ancestor way back when, while sniffing around for a female CA in heat, may have all of a sudden started pondering their existence. But why would I assume such a thing?

Again, I'm not claiming it's impossible.

Wouldn't you agree that it's a bit shaky?

And not to mention the fact that there's just no proof that early man made up the concept from imagination.

Again, not claiming an impossibility. But why should I consider it beyond a mere suggested possibility?

...this is generally a silly semantics argument.