One strand of development in the Greek view of nature was largely independent of Aristotle’s work, however, and this concerned the role of mathematics. Mathematics itself developed considerably, becoming more creative, rigorous, and systematic in the work of Apollonius, Archimedes, and Euclid. The major application of mathematics to the natural world was in astronomy, owing to the high degree of regularity in the celestial motions and large amount of observational information accumulated. Although the Babylonians had employed sophisticated mathematical algorithms to this problem, the great innovation of the Greeks was to devise what we would call mathematical models, i.e. to devise a theoretical concept of how the sun, moon, and planets must move, work out its mathematical implications, and compare these to the actual motions. From the early work of Eudoxus to the culminating system of Ptolemy, this project dominated astronomy, but the attempts of Aristotle’s followers to give a physical explanation for these basically mathematical pictures gave rise to issues that would survive the end of antiquity. An aspect of the Greek concept of nature was forming that did not quite cohere effectively.
The work of Archimedes in statics and hydraulics was a rigorous application of mathematics to natural phenomena. Such work was a more modern-looking and less mystical version of the old Pythagorean concept. Although the investigations of Archimedes were brilliant successes, they were too isolated to greatly affect the general Greek concepts of nature (though they did sow the seeds of much later science). Archimedes also performed some practical engineering work, and the practice of engineering and applied science (metal working, agriculture, etc.) in general formed another aspect of the Greek approach to the world in late antiquity. The most famous practitioners in this tradition were Vitruvius and Hero of Alexandria (the latter best known for his small steam-driven device). Yet another practical tradition that continued to make progress in improving knowledge of the world was found in medicine, including the knowledge of human anatomy discovered by dissection. But the knowledge resulting from these kinds of practical pursuits, though important, was not incorporated into any larger vision or theoretical structure. Such knowledge must have influenced the Greek view of nature indirectly, but it remained fragmentary and isolated, not really contributing to a new coherent concept of nature.
This latter project remained the province of philosophy, either that of Plato and Aristotle (and their commentators) or that of three new rival schools that arose: Epicureanism, Stoicism, and Neoplatonism. None of these philosophies, however, regarded understanding the world as their highest priority. Epicureanism and Stoicism were both primarily ethical philosophies, concerned with the right way to live; both devised concepts of nature as a means toward the end of promoting virtue and equanimity in their followers. Neoplatonism was primarily a mystical philosophy with the aim of transcending the material world altogether, and thus did not put much effort into nature philosophy, although some Neoplatonists explored further the idea of mathematics as a more fundamental reality underlying physical nature itself. The Epicureans and the Stoics did put forth substantial views of nature, and these views were almost completely different from each other. Epicurus was a materialist and an atomist in the tradition of Democritus. The major innovation of his system was the introduction of chance (“swerve” in the paths of the atoms) in contrast to the totally deterministic (reason and necessity) system of Democritus. The motivation of Epicurus in adding an element of chance to atomism was to allow free will and therefore moral responsibility to the system. The Stoics, whose views varied somewhat with different teachers and times, adopted the old idea that a void could not exist; all space was filled by their two continuous and intermixing substances, an inert material substrate and an animating vital spirit (pneuma) that gives form in accordance with reason. In the Stoic conception, the universe with its pneuma is a living being, of which the human with its soul is a microcosm. The pneuma is corporeal, and in that sense Stoicism is also materialistic even though forms arise through the action of an Intellect, unlike the Epicurean idea of only blind forces acting.
Nature in Chinese Thought
Although Chinese thinking about nature was not entirely static, it was remarkably stable over a period of two thousand years. In traditional Chinese culture, the elements of philosophy, religion, science, social structure, and political order were highly integrated, so looking at their concept of nature in an isolated way is not sensible. Another complication is the somewhat varying influences of Confucianism, Taoism, and Buddhism on their attitudes toward nature. Yet another complication is the presence of occasional voices and movements that lie outside the main current of cultural thought in China, such as the naturalistic tendency found in the Mohist movement or the skeptical writings of Wang Ch’ung. We can present here only a brief and simplified description of the major trends in Chinese thought concerning nature.
One of the primary cornerstones of Chinese thinking is that it is correlative rather than causal when considering the relationships between events, things, ideas, etc. There are connections between things (north and feminine, for example) that are not either causal or logical relations but rather these connections are said to exist inherently in the make-up of the universe; such correlations are simply a part of the way things are, not the result of anything acting on the things or mutual actions of the things on each other. One major consequence of this correlative thinking is the importance of microcosm/macrocosm interpretations of nature. “A basic feature of systematic thought about the external world as it arose in China is that the body and the state were miniature versions (not just models) of the cosmos.”19 In this view, the human is a microcosm of the entire universe, the macrocosm, and there are a host of correlations between the two. Human society, identified with the state, is also a microcosm of the macrocosmic world. These three realms (human, society, cosmos) are linked together by many particular correspondences and also linked together by the person of the Emperor, who must perform the correct rituals to maintain order in the cosmos and in the society. Beyond its political implications, the microcosm/macrocosm view influenced the understanding of natural phenomena. Various organs and parts of the body are associated with parts of the greater world and their processes and functions operate in the same manner. Just as stagnant water gives rise to stench and decay in a pool, so stagnation of the body’s vital fluids leads to illness in a person. The emphasis is much more on process than on structure (anatomy in the body, physical characteristics in the world). “…organs and tissues figured in medical doctrines as mere correlates of the body’s systems of functions, mainly useful in diagnosis and in schemata that aligned parts of the body with physical features of the macrocosm. […] circulation is fundamental not only to the body’s growth but to its maintenance, irregularities in it are responsible for pain and disease. Somatic blockages are analogous to failures of circulation in the universe and the state.”20 In astronomy, the order observed in the celestial realm exemplified the desired order in a properly functioning Confucian society/state, and the particular sky events as recorded or predicted formed the basis for the calendar, presented by the Emperor as a mandate for the existence of a new year. Clearly, the Chinese interpretations of astronomical phenomena were heavily influenced by the microcosm/macrocosm view.
There remains a question of what governs all these correlated events and ideas. Once again, the answer involves inherent properties and relations as opposed to external causal influences. More specifically, the Chinese conception of nature is an organic one, in which processes and events unfold in accord with their inherent tendencies, and relationships are maintained by preexisting harmonies. “…the philosophia parennis of China was an organic materialism. You can illustrate this from the pronouncements of philosophers and scientific thinkers in every epoch. Metaphysical idealism was never dominant in China, nor did the mechanical view of the world exist in Chinese thought. The organicist conception in which every phenomenon was connected with every other according to a hierarchical order was universal among Chinese thinkers.”21 No central directing intelligence is required or found in this paradigm. Changes and processes simply occur as they are meant to, in conformance with their own inner natures and in relationship to all other changes and processes occurring similarly. Immaterial agents and entities are not a part of orthodox Chinese philosophy, but this fact must be qualified in two ways: First, a strain of older animistic thinking did survive in Chinese culture and sometimes became integrated into the orthodoxy. For example, to say that the inner nature of water is to flow downhill can be closely related to (or even shade into) the attribution of a “desire”