"God"
If you read any cultures' religion, viz. God, Allah, etc., and substitute, "Mind", that's what they were really talking about.
No person nowadays - humanity for the most part - believes that the seasons are caused by Gods or Goddesses, that rivers are guarded by river-sprites, that there are ghosts. It has abandoned the dream world, save for one thing - God with a 'capital G' (even though humanity in general has already abandoned all the lesser, small g gods and goddesses). Even those who say they don't have an interest in religion or God - having no particular attraction to religions or the idea of God - when they hear someone else talk about the characteristics and attributes of their God, it affects them, too - they have no choice. Because it is the brain, talking about itself, and everybody is immediately affected by that.
Why can't it realize what it's doing?
It's impossible for it to do so!
When the brain is talking about God, it is talking about itself. It's realized what it's doing regarding the lesser gods of mountains, trees, rivers, animals, seasons, etc., but regarding the greater big G God, no way. And there's no evidence whatsoever that human minds are changing in that regard - certainly not in the last 6000 years. The only answer must be, that the human brain (mind) is literally incapable of talking about itself, while knowing it's talking about itself.
You can't talk other people out of believing in God. There are certainly some who are interested, like atheists and agnostics. But note: Atheists are always well-educated, very sophisticated. You never find semi-aboriginal peoples, uneducated, who are atheists or agnostics.