I only have one thing in common with most people I know. Which specific interest, appreciation, commitment, or passion it is varies, but it’s usually only one. I looked around the parking lot when I arrived at the climbing gym today. There were many hybrids, some vans and SUVs, as well as a smattering of sports-cars (an S2000, FC RX-7, STI, Z4). I thought that climbing must appeal to a wide base of people. Some would like it for the oneness with nature, others for the sport or strength aspects. Someone who drives a Prius usually has very little in common with someone who drives a modified RX-7, but one commonality is enough to bring them together.
Outside of work, I wouldn’t know any of my co-workers. Outside of church, I would be unlikely to know any of the same church people. And of course, offline, I wouldn’t really know anyone. Even if we like what we like for very different reasons, one connection is enough to build common ground.
I’m glad I don’t have everything in common with anyone else. That variance is what opens my mind to new ideas, and is what keeps things interesting.