Briefly that everything happening in the present can best be understood by applying
knowledge of how events unfolded in past societies. For example some historians have noted that the rule of societies tends to pass, over many centuries, from monarchies (kings) to oligarchs (aristocrats) and to the people (democrats) and then back to monarchs. Another example of historicism is developed by Karl Marx who supposed the power of the aristocrats was replaced by that of traders and manufacturers (bourgeoisie), and they in turn were replaced by the workers. This theory inspired the Russian and Chinese Revolutions of the 20th century. In his book The Poverty of Historicism, Karl Popper suggests that advances in scientific knowledge could allow humans to develop
open and free societies for as long as they wish and thereby escape from historicism.