Exploit the architecture of human cognition
And after all of this inspiring stuff, I am going to offer some information I have come across, and that is going to sound dry and heartless in comparison. 
There is a concept at the crossroads of evolutionary biology, anthropology and psychology called cultural evolution. The idea is that, in humans, culture and biology intertwine dynamically: evolutionary pressure makes us evolve mixed packages of genes and culture that make us fitter for survival. These packages repurpose and harness pre-existent packages. If you want to know more, this book is a fantastic introduction.
Researchers in this area have figured out why humans have evolved rites of passage, which can be very costly (in some tribes, young men especially have to go through gruesome trials to become full members of the tribe). So where’s the benefit? The benefit is that these rituals cement the tribe’s cohesion, making it more fit to withstand intergroup competition, a major driver of human evolution (and suspected to have been a driver of non-human primates before we came around). How can rituals cement cohesion across participants? They harness certain biases in human cognition. For example, it has been found that doing things in sync enhances the propensity to cooperate. Consider the following experiment.
- Participants are randomly divided in two groups. People in group A are asked to perform a simple physical act in sync with each other, like clapping hands. People in group B are asked to per form the same act, but not in sync.
- All participants are asked to play a simple game where they need to choose between a "cooperate" and a "defect" strategy, like the Prisoner's dilemma.
- Members of group A have a measurably higher probability to cooperate.
So, to make strangers connect, a sensible strategy seems to be to “think like a hacker” and exploit the biases in human cognition, such as the tendency to cooperate more with people you have done something in sync with. A major bias is that we seem to be hardwired for forming groups. It is very, very easy to make humans behave like a group – check out Wilfred Bion’s work for that.
Obviously, this same kind of hacking is successfully used every day by racist groups, who succeed in making people hate and despise other people just like them, who have never hurt the haters and whom said haters do not even know anyway. Like the Force in Star Wars, human cognition has a dark side… but you guys, I’,m sure, will stay away from it.
