First heard of self-organizing criticality in 1990 by a professor when I first got to college…. and unfortunately he wasn’t my professor. It was too soon for me to attend his courses, which were higher level and I never made it past 1.5 yrs due to money. But I _really_ wanted those courses. Thankfully the growth of the Internet from then through now has allowed me to learn as much of this stuff as I can on my own, and when you think in terms of self-organizing systems, saddle points, chaos, all related systems in their non-linear fashion… and such… it becomes how you see and understand things intuitively, even if you don’t have the math behind it handy.