You imply that this is odd.
You confuse a physical state with a tendency. Children are born small but are born with a tendency to grow larger. Children are born knowing nothing but with a tendency to learn. A child that did not grow or learn would be considered odd, yes.
It is a scientific fact that the human brain is wired toward superstitious thinking....
I have seen no proof of this. The human brain is curious and seeks out explanations for why reality is the way it is. This tendency often leads to false ideas about reality. This is true even for science.
...which lends itself towards theism
No. All initial inquiry can be labeled "superstitious thinking". It is ad-hoc to bunch theism in with "superstitious thinking" to suit your argument. Even science has led us to wrong beliefs about reality. "Superstitious thinking" is wrong thinking. Both science and theism can fall under this banner. It is your bias that makes you equate theism with superstition.
You can't be born neither an atheist nor a theist. There is no middle ground between the two. You are either one or the other.
Not true. Children are BEFORE the determination of theist or atheist, just like Schrödinger's cat, we cannot say whether they are theist or atheist, so they are neither. A person cannot be unconsciously atheist, as atheism requires a knowledge of theism, thus the name "a-theist". Without theism, the definition of atheist makes no sense.
Atheism is not simply an absence of theism, it is a rejection of theism. In newborns, there is no theism, and thus nothing to reject.
I am proposing that theism naturally developed out of the myths and superstitions of ancient humans.
Even science developed out of the myths and superstitions of ancient humans! Both science and theism have had to separate and distinguish themselves from the old myths and superstitions of ancient humans. But all inquiry "lends itself" to superstitious" thinking. It is just easy for your argument to label all theism as "superstitious thinking", but unfortunately for you, that categorization is also wrong.
Left to our own devices, we invent myths and superstitions.
Then it is convenient for your argument that you have already labeled theism as "myths and superstitions"! Getting to conclusions by means other than logic makes for poor arguments.
Try this....
Left to their own devices, a group of people would merely be superstitious and would most likely develop some sort of science as a crude explanatory model of the world (you know, as actually happened in human history).
...Is the above true? of course it is. You are trying to shoe-horn theism into "superstitious thinking" when science also fits the bill!
It is impossible to be completely, 100% rational. No person is, ergo every person has some level of irrational thinking.
You contention has not been about thinking, but "superstitous thinking", which you equate with theism. So please clear this up for me. Is the following a correct representation of your position?
It is impossible to be completely, 100% non-superstitous. No person is, ergo every person has some level of superstitous thinking.
1. If you say the above is true, you then admit that superstition is NOT the exclusive domain of theism, but if you say the above is untrue, then 2. You DO equate theism with superstition.
1 undercuts your current argument, and 2 is obviously an atheist bias.
The propensity for superstitious thinking is innate in us, just like the propensity for language is innate in us.
That is well and good, but you go further and substitute "theism" for superstitious thinking" in your argument. That is a fallacy. A perfect example using your claim above would be if you substituted "English" for language.
The propensity for superstitious thinking is innate in us, just like the propensity for English is innate in us.
Both substitutions render the statement incorrect. Superstitious thinking is not what is innate in us, curiosity is what is innate. Just as English is not what is innate in us, language is what is innate. It is just as illogical to substitute English for language, as it is to substitute theism for superstitious thinking, when talking about "innate qualities" in us.
Calling a baby an atheist rests on the incorrect definition of atheist as "without belief". But without belief in what? "Without belief" becomes comparative, and is thus irrational in a system devoid of theism, which is what a baby is.
For example, calling someone a-moral loses all rationality in a system lacking morality. Lacking morality makes sense only if there exists morality in that system. Babies are born neither atheist or theist. When the child takes up a belief in God, he becomes a theist, when he rejects a belief in God, he becomes an atheist. Before then, he is neither.
