Dialectics is, in marxism, the movement of material things and ideas through internal contradictions.
The word "dialectics" initially meant, primarily, the art or the science of argumentative discussion.
For Plato, dialectics is, firstly, the art of extracting all the positive and negative consequences contained in an idea or principle. Secondly, it is the rational movement of the mind which ascends by successive stages, from perceptible data to ideas, the eternal and immutable principles of things, and, finally, to the primary idea of all, the idea of the Good. Since for Plato ideas are the only reality worthy of the name, dialectics or the science of ideas comprises science itself.
For Hegel dialectics is the movement of ideas through the successive stages of thesis, antithesis and synthesis until the absolute idea is attained.
For Marx and Marxists, dialectics is no longer the movement of ideas, but rather the movement of things themselves through contradictions, of which the movement of the mind is but the conscious reflection. An extensive study of Marxist dialectics can be found in the fourth part of the present work.