If you could teach everyone in the world one concept, what concept would have the biggest positive impact on humanity?
Critical thinking
Absolutely! It appears that critical thinking is a lost art. Too many people are afraid to challenge authority or the status quo. Need evidence, just look at who is President.
I would like to say how to manage their retirement fund but given that 9 out of 10 humans on earth live in the developing world it doesnt matter to the bulk of humanity. Kinda hard to start talking about portfolio re-balancing with a 3rd world rice farmer who sleeps with their ak-47.
Maybe basic sewing?
Every human should do LSD once.
Just kidding, kinda....I would say love and forgiveness.
I would at least try to teach them that their belief or opinion (be it theological or otherwise) is not necessarily better than the equally dearly held belief of others. That unshakable belief in superiority shuts down any sort of chance conversation or compromise.
You're a person.
You aren't any better or different than anyone else.
I don't care about who you fuck, how you identify your fucking, what your skin color is, what your monetary value is, or who your imaginary person in the sky is.
You're a damn person.
Stop with the bullshit semantics
And get over yourself.
Let's save the planet,
Terra-form Mars,
And get rid of the white man by interracially reproducing.
????
The concept of reality. Believing in things because it feels good or for any other reason than evidence that it is true is damaging. Reality is the only way forward and the only honest way to live
Critical thinking. It would solve a lot of the world's problems.