In music, people find one form of compositions boring, then new compositions are heard, people delight the difference. When most new compositions are heard in this new form, people want variaty again…
The development of painting should be the same.
Civilisation denasties rough history: united nation, break up into independent states due to corruption and misgoverment and econimic failure, and is what people want; then after a period of bloody wars, united again, and is what people want.
Science subjects: a dominat theory set the frame for a particular period, problem encountered, new theories emerge - chaos. Soon, one of the new theories comes to sort it all…
Can all these be summed up as the cycle? Reason: changes are made by people, since people want to change - people get sick of unity and confused by variaty.