I read this great book recently Sapiens: A Brief History of Humankind. These are the kind of things it talks about...
The modern human is mostly homo sapiens (about 92%, the rest of the dna is neanderthal). But apparently, homo-sapiens is not an evolution of the neanderthal or the homo-erectus. All great ape species walked the earth at the same time up until 50-60 thousand years ago. And it looks like the others (neanderthal man especially) were as advanced as the homo-sapiens. Neanderthals had language, played musical instruments, painted figures on cave walls etc. Also they were stronger than the homo-sapiens.
But at some point the homo-sapiens dominated the whole world massively, driving the other species to extinction (most probably by massacres).
How did that happen? The book suggests that it is because of this;
By JDuckeck - Own work, Public Domain, https://commons.wikimedia.org/w/index.php?curid=3843458
The idea is that something in our homo-sapien brain flicked, possibly a genetic defect and we suddenly started to believe in our own bullshit. The importance of this figure is that nobody could possibly have seen that lion-man anywhere. The artist must have imagined it. That vivid imagination, goes the claim, is what gets humans come up with groups larger that their immediate acquaintances (typically of 150 people).
Equipped with this superpower, we went ahead to form larger groups of individuals who believe in the lion-man-king. People who don't know each other that collectively believe in some narrative working together (and killing everybody else who don't) We know the rest as history of kingdoms, crusades, empires, religions, football teams etc.
Now I know this is a very long introduction. But here is what I really want to say;
If you want to keep a group of people together, make them behave like a group, you need a narrative. You need some story that everyone buys into. This applies to countries, religions, unions and also project teams.
Without a story, we are nothing.
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