The Concept of Natural Order in the Système de la Nature

D’Holbach examines the notions of order and disorder in Chapter 5 of the first tome of The System of Nature. In his classic History of Materialism Friedrich Lange summarized this Chapter, emphasizing that order and disorder are only relative to subjective human evaluations though we may interpret order as objective if we think of nature as the necessary system of causes and effects. A more accurate reading of d’Holbach’s texts shows that he conceived an objective notion both of order and of disorder: the objective order of nature is the absolute deterministic system of causes and effects; the objective disorder of nature is the change of a preceding state of things, both of them equally depending on the absolute order of nature. Even human prejudices about order and disorder are objectively grounded as they depend on the relation between the natural course of events and the equally natural drive of each individual to survive and to enjoy pleasant sensations. The subjective notions of order and disorder become sources of error only when they are employed by human imagination to describe the whole universe, thereby concealing the true necessary order of nature which is conceived by reason. Following upon the main distinction between order as the necessary structure of nature and the subjective ideas of order and disorder, d’Holbach employs two arguments to criticize natural theology: the first is a typical retort to the argument from design, a retort which demonstrates how physical theology is based on a partial consideration of what men judge to be naturally ordered to their advantage; the second is an ‘argument from immanence’ aimed at showing that the objective necessary order of nature cannot be explained merely by ascribing it to the more obscure notion of the Deity. Immutable necessary order is the cornerstone of d’Holbach’s metaphysics of nature. A strong determinism underlies all the transformations which are due to the energy of motion belonging to the essence of matter. Natural changes are infinite as the properties of bodies can combine in endless variations. These three features of d’Holbach’s view of nature (necessity, energy and infinity) may be conceived as mutually consistent: the unchanging necessary laws apply to an infinity of different factual situations and this generates a constant becoming which unfolds as an endless deterministic series of events. D’Holbach’s view of nature, however, cannot be reduced to these three concepts. A further aspect impairs the coherence of his system: our limited knowledge of the causes and natures of motions. D’Holbach admits that the inner constitution of bodies, being imperceptible, is unknown, and therefore many causes of motions remain unknown too. This epistemic limit, coupled with the adoption of Leibniz’s principles of indiscernibles, appears incompatible with the strong metaphysical determinism asserted by d’Holbach merely on the assumption that every action of each body must proceed from its essence, according to the axiom ex nihilo nihil. A final assessment of d’Holbach’s philosophy is suggested: despite the inconsistencies of his metaphysics of nature and the problems related to its determinism, d’Holbach’s philosophy deserves to be appreciated in the history of western thought because it represented the first materialistic and atheistic system, opposed to the philosophical ‘ancien régime’ of theological metaphysics which had hitherto dominated the philosophical tradition.