I'm with Keynes here.
Human irrationality is hardwired into the species, rather than something we can "grow out of". Hope in this regard is no different from hoping for the 2nd coming of Jesus: a comforting illusion.
We do teach them that from an early age in many countries, it's just that we cannot escape our nature any more than other animals can.
Humans aren't divided because of pernicious doctrines, we are divided because we evolved living in small groups mediated by personal relations while being frequently threatened by outsiders. Unless you start from the irrational perspective that humans are, by default, united unless there are things that divide us, religions, ideologies and nationalities are massively unifying forces. The problem is humans can only be unified so far before coalitions and identities fracture again.
Humans aren't irrational because they are indoctrinated into irrational beliefs, irrational beliefs are ubiquitous because humans are irrational (or, at best, only intermittently rational).
This is what Keynes was getting at: We can't solve problems by expecting people to behave rationally.
Here is a fun example of what we are fighting for with an I/we.
It is a case of in the end different cognition and feelings.
Someone regardless of religion or not: I/we can for all humans for all time do the universal right/correct behavior for all case of human behavior.
Me. I can't
That someone: Then you are a negative/a negative will happen to you.
Me: No, not in all cases.
That is in a sense the end game, and for some religious people it is about an eternal negative, Hell.
For the non-religious Ayn Rand did a simple one:
"All thinking is a process of identification and integration. Man perceives a blob of color; by integrating the evidence of his sight and his touch, he learns to identify it as a solid object; he learns to identify the object as a table; he learns that the table is made of wood; he learns that the wood consists of cells, that the cells consist of molecules, that the molecules consist of atoms. All through this process, the work of his mind consists of answers to a single question:
What is it? His means to establish the truth of his answers is logic, and logic rests on the axiom that existence exists. Logic is the art of
non-contradictory identification. A contradiction cannot exist. An atom is itself, and so is the universe; neither can contradict its own identity; nor can a part contradict the whole. No concept man forms is valid unless he integrates it without contradiction into the total sum of his knowledge. To arrive at a contradiction is to confess an error in one’s thinking; to maintain a contradiction is to abdicate one’s mind and to evict oneself from the realm of reality."
—Ayn Rand Lexicon
The beauty of that one is, that you are not supposed to ask the following question: If you are in reality and I am not, how do you know from being in reality that I am not in reality?
That answer is that I am not really objectively relevant because I am irrational.
