This is the first in a series on the history of dialectical philosophy.

The central idea of dialectics is the unity and struggle of opposites, that is, contradictory tendencies that are tied together and cause things to change and develop. Philosophy based on this idea is essential to the science of communism. Karl Marx and Frederick Engels were the founders of communist philosophy, but they did not start from scratch. They borrowed ideas from a long history of dialectical thought that dates back at least 25 centuries in Europe and was developed independently in China and India. We can only mention here the earliest and latest stages of that history.
The earliest major dialectical thinker in European history was the Greek philosopher Heraclitus, who lived about 2500 years ago in what is now western Turkey. Heraclitus said that conflict is universal, "the father of everything," and makes some people slaves and others free. Heraclitus emphasized that opposite qualities of things exist at the same time: "Seawater is very pure and very foul water; for fish it is drinkable and life-sustaining, for people it is undrinkable and deadly." "Writing is both straight and crooked." He recognized that things have a connection to their opposites, a connection that turns back on itself, "like a bow or a lyre."
Heraclitus drew the conclusion that everything constantly changes, that it isn't possible to step in the same river twice, since different water is constantly flowing by. He also said that things tend to turn into their opposites: disease turns into health, weariness into rest, hot into cold, etc.
Heraclitus' ideas were not well received by most other ancient Greek philosophers. They wanted to see stability in the natural world and social life, trying to make it plausible that the slave-owning class they represented would continue to rule indefinitely. Criticism by Heraclitus' opponents spread his ideas and allowed them to influence later generations.

Hegel's Big Contribution
The last major figure in the development of dialectical philosophy before Marxism was the German philosopher G. F. W. Hegel, who died in 1831. Hegel understood that he was following in Heraclitus' footsteps and wrote that "there is no proposition of Heraclitus which I have not adopted in my logic."
Hegel was inspired by the French revolution and worked closely with people fighting against the feudal monarchy in Prussia. He saw that conflict and contradiction are found everywhere, and that things and processes can only move themselves forward because they contain contradictions. While contradictions within something can last a long time, they move toward their own elimination. The process of a contradiction eliminating itself is called "resolution." Hegel argued that resolving contradictions gives rise to new situations, which will contain new contradictions that require resolution.
Hegel made a profound and thorough (but very difficult) study of contradictions and other topics in dialectics, and applied these concepts to nature and society. This was the reason that Marx declared that Hegel was a "mighty thinker" and regarded himself as Hegel's pupil.
Despite Hegel's contributions, Marx and Engels found two serious errors in Hegel's philosophy. The first was that Hegel was not a materialist. Materialism says that material objects and structures are the basis of our thinking about them, thinking that represents those things more or less correctly. Our ideas about reality come ultimately from practical interaction with it.
Hegel did not see matter as the basis of thinking, but thinking as the basis of material things. He claimed that thinking is the "essential nature" of things, that thinking "goes out of itself" into things, and that "logical reason" holds the properties of things together and forms their unity.
Marx rejected this idealist view as the reverse of the truth. He said that Hegel's philosophy was standing on its head, and needed to be turned over to stand on its feet, on material reality.
Hegel's second big mistake was directly about dialectics. Hegel maintained that contradictions could be resolved in ways that preserved both opposite sides in a "higher unity," a synthesis that made them no longer contradictory. Marx argued that this is dead wrong about contradictions in the material world of society and nature. These are resolved by "fighting to a decision," with one side defeating the other. As we will see in future columns, this idea is the core of communist dialectics, with profound implications for the fight for communism.

The oldest known Chinese book, the Yihking (1143 BCE) included the ideas – fundamental to dialectics — that everything is always changing and that opposites are interconnected. Examples included Yang and Ying, heaven and earth, male and female, light and dark, strong and weak, father and mother. Changes in "heaven" and on earth were explained through the development of these polar opposites.
The philosopher Lao-Tse (or Laozi) wrote that "when everyone on earth declares beauty beautiful, ugliness is thereby postulated. When everyone on earth recognizes the good in goodness, thereby is evil postulated. Being and non-being produce each other. Heavy and light complete each other. Long and short compose each other. High and low invert each other. Voice and tone wed each other. Before and after follow each other." (around 600 BCE)
Mo'-ti' (or Mozi), a carpenter and inventor, brought materialism into ancient Chinese dialectics. For example, he wrote that "My view of being and non-being rests on what the actual experience of the eyes or ears of the people accept as existent or non-existent, that is, on what is seen and heard." (around 400 BCE) It shouldn't surprise us to learn that Mo'-ti' took a revolutionary attitude toward the ruling class of his time and that he believed that people could change their circumstances and direct their own lives.

Next column: Marx and Engels initiated communist philosophy.