Dialectics of Nature (Excerpts)

Wellred

Core Argument

These excerpts from Engels's unfinished magnum opus constitute a sustained materialist inversion of Hegelian dialectics, arguing that the laws of dialectics are not imposed upon nature by thought but abstracted from nature and history themselves. The three fundamental laws—transformation of quantity into quality, interpenetration of opposites, and negation of the negation—are presented not as a priori categories but as generalisations derived from empirical scientific investigation.

The law of quantity into quality receives its most triumphant demonstration in chemistry, where different proportions of identical elements produce qualitatively distinct substances. Engels cites Mendeleev's prediction of gallium by atomic weight as an unconscious application of Hegel's law, comparable to Leverrier's calculation of Neptune's orbit. The same law operates in physics—water becoming steam or ice at specific temperatures—and extends into biology and society. Hard and fast lines between categories are incompatible with evolutionary theory; dialectics alone, recognising no unconditional "either-or" but also "both this-and-that," corresponds to the actual movement of nature.

The polemic against metaphysical thinking extends to the categories of identity, chance and necessity, and induction. Abstract identity (a = a) is inapplicable to organic nature, where every cell is identical with itself yet constantly becoming distinct. Mechanical determinism, which denies chance entirely, degrades necessity to the production of the merely accidental. Darwin's achievement lay in taking infinite accidental differences between individuals as the basis for shattering the old metaphysical concept of species. Induction is not infallible—its results are constantly overturned—and belongs together with deduction. Human activity, not mere observation, proves causality: if we can produce an effect by setting up its conditions, we establish a causal relation.

Engels attacks Nägeli's claim that we cannot know qualitative differences or the infinite. The cognition of the infinite proceeds only through an infinite asymptotic progress, composed of finite human minds working side by side, committing blunders and pursuing false paths. Matter is nothing but the totality of material things; motion nothing but the totality of perceptible forms of motion. The eternal laws of nature become transformed into historical ones; official physics, chemistry, and biology are exclusively geocentric. Nothing remains absolutely universally valid except motion itself.