When we reflect on the origins of Marxism, we immediately think, with good reason, of German philosophy, English political economy, and French socialism and political currents, all of which are fundamental elements in the gestation of scientific socialism.
However, Marx and Engels not only witnessed political revolutions throughout their lives; During the nineteenth century, scientific and technological progress also gave birth to comparable achievements in the field of natural sciences: the birth of modern chemistry, Darwin's evolutionary theory, the discovery by Pasteur and others of a whole microbial world ... it became Therefore, it is essential to elaborate, in the light of the dialectical character of the new data obtained by the natural sciences, a dialectical materialist conception of nature that assumes such achievements and, absorbed as Marx was in the drafting of Capital, it was Engels's turn face such a challenge. And so, it was he who, in Dialectics of Nature, elaborated the fundamental postulates on matter and motion, demonstrating that "dialectical laws are real laws of the development of nature, and, therefore, they are also valid for the natural sciences theoretical ».
In polemic against the various anti-scientific tendencies in force among the scientists of the time, impregnated with the conceptions of the dominant ideology - vulgar materialism, metaphysics, idealism, agnosticism, mechanism, spiritualism - Engels interprets the most important conquests in a new way. of natural sciences. In doing so, he addresses problems and categories of dialectics, such as causality, necessity, and chance; classification of the forms of judgment; relationship between induction and deduction; function of hypotheses and many others. In this pioneering work, Engels also formulates the definitive theory about the role of work in the process of hominization, and of practice and production in the development of science.