** Below is the same basic argument with revisions due to flaws and weaknesses that were exposed through criticism. Thank you to everyone who contributed in the discussion that has led me to a more sound argument. **
Men are not naturally "Atheist", they become Atheist. To claim that a man is naturally Atheist is untrue unless the concept of God is automatically pure nonsense to him. Take the youngest child with the earliest stage of intellect in place. When you try to explain God to them, you are not met with immediate distrust and rejection. They have the natural capacity to understand the concept of God. Now try to explain that an engine exists inside a car and makes it go. Numerous questions and even mistrust may follow. They have the ability to be taught and to learn what an engine is, but the built in capacity to grasp the concept of an engine is not there as it is with God. We have a natural schema built in for knowledge of God. This is common and easy to access empirical data.
If this schema was not built in, then men would see the concept of God as pure and un-intelligible nonsense from the earliest age. Sure they can be "indoctrinated" but eventually, ideas of Santa Claus or Unicorns are seen as untenable because evidence is lacking as well as a schema. If this schema for God were not there, men would not see fit for constant written or spoken denial of God. So men, in a sense, become Atheist. They deny knowledge that they already knew to begin with. So the Atheist who uses any energy to deny God’s existence ends up confirming his own innate knowledge of the very thing he wishes to deny. In other words, with every word written and spoken in an effort to deny God’s existence, the Atheist proves he was born with a schema for knowledge of God that he is now opposed to. Because if the Atheist’s natural state of mind was “Atheist”, then the concept of God would be so foreign and stupid to him, he would not waste a single second denying such nonsense.