Any kind of class divide that grows over time is bound to become violent. A stable society may have classes, but these classes have to remain relatively the sam

Any kind of class divide that grows over time is bound to become violent. A stable society may have classes, but these classes have to remain relatively the same for a long time (even if there is movement of people between classes). For example, medieval society was unjust, but at least the difference between classes was stable over several centuries. In the modern world we now have a class of owners that increase their wealth astronomically in a few years, while most people are seeing their incomes stagnate or decrease.