There aren't a lot if you consider your immediate social circle, but social media allows us to reach millions of people and increases our experience database. In all my social circles of maybe a couple hundred people over the last 40 years I have 2 acquaintances that were considered dangerous. One was a husband that fell into meth use, and another was a narcissist boyfriend they couldn't take no for an answer. My extended social circle ranges from nurses and doctors to hairdressers to real estate agents to retired PD to cancer researchers to the trades to high tech folks and everything in between.