Many years ago I took (oddly) a physics class called (iirc) "Self Organisation" while doing a year abroad in Germany. Despite being a quite small class, it really inspired me from the perspective of self organizing systems.
I find structures like conways game of life, or slime mold or sand dunes to be fascinating for this reason. That from unit simplicity can emerge aggregate complexity, imitating facets of nature.
This stuff is fascinating, but also very humbling. Conway, fractals etc is truly a testament to how few and simple ingredients can create structures that are virtually impossible to analyze and predict without running the simulation. It speaks volumes about our limitations.
I find structures like conways game of life, or slime mold or sand dunes to be fascinating for this reason. That from unit simplicity can emerge aggregate complexity, imitating facets of nature.