On the lighter side, I came across this article explaining, based upon a new engineering study, detailing how bridges can suddenly become unstable. “If enough people are crossing by foot, each walking at their own natural speed, they transfer so much energy into the bridge that it may start to oscillate. Then, as each individual walker adjusts their steps to try not to fall, they destabilize the bridge even more. Bridge wobbles can lead to mass panic -- in 1987, on the 50th anniversary of San Francisco's Golden Gate Bridge, 300,000 celebrants tried to cross and the bridge groaned and swayed, causing people to panic, vomit, and start throwing bicycles and even baby strollers into the ocean to lighten the bridge's load.”
Somehow there is a metaphor buried in all that about human society today, which too is becoming unstable as critical thresholds are also being reached.