Aristotelian natural philosophy is the body of theory developed by the Greek philosopher Aristotle (384-322 BCE) concerning the natural world, encompassing what later traditions would separate into physics, cosmology, biology, meteorology, and the philosophy of science. It is grounded in qualitative rather than quantitative analysis, organized around the concept of substance, form, matter, and four causes (material, formal, efficient, and final), and posits a teleological universe in which natural things move and change in accordance with inherent ends. For roughly two millennia it constituted the dominant framework for natural inquiry in the Greek, Islamic, and Latin European intellectual traditions.

Aristotle's natural philosophy is set out principally in the Physics, On the Heavens (De Caelo), On Generation and Corruption, the Meteorologica, and the biological works. Central to the system is the distinction between matter (hyle) and form (morphe), and the account of change as the actualization of potential. Aristotle identified four causes as necessary to explain any natural phenomenon: the material cause (what a thing is made of), the formal cause (its defining structure or essence), the efficient cause (the agent or process that brings it about), and the final cause (the end or purpose toward which it tends). The final cause - teleology - is particularly distinctive: Aristotle held that natural processes are directed toward ends without requiring conscious design.

In cosmology, Aristotle proposed a geocentric, finite, and eternal universe divided into two regions with fundamentally different physics. The sublunary region - everything below the orbit of the Moon - is composed of four elements (earth, water, air, and fire), each with a natural place and natural motion: earth and water move downward toward the center; air and fire move upward. In the superlunary region, celestial bodies are composed of a fifth element (aether or quintessence), which undergoes only uniform circular motion and is free from generation and corruption. This two-region cosmology had direct implications for later astronomical models, including its relationship to the Tychonic system and the Ptolemaic and Copernican alternatives it preceded.

Aristotle also developed influential accounts of place, void (which he denied exists), time, continuity, and the infinite - all treated in the Physics. His rejection of the void and of action at a distance shaped medieval and early modern natural philosophy, and the effort to account for projectile motion within his framework produced sustained debate, eventually yielding the impetus theory associated with John Philoponus and later Jean Buridan.

In biology, Aristotle made extensive empirical observations and produced systematic classifications of animals, grounding species in form and function. His biological teleology - the idea that organisms have parts because those parts serve functions essential to the life of the whole - remained influential well past the period of his cosmological eclipse.

Aristotelian natural philosophy was systematized and transmitted through the Peripatetic school, commentated upon extensively in late antiquity (notably by Alexander of Aphrodisias and Simplicius), and incorporated into Islamic philosophy by figures including Avicenna (Ibn Sina) and Averroes (Ibn Rushd). The Latin translation movement of the 12th and 13th centuries brought the bulk of Aristotle's natural works into western European universities, where they were integrated - often with significant tension - into Christian scholasticism, most influentially by Thomas Aquinas. This Aristotelian-scholastic synthesis became the dominant framework of university natural philosophy until the 17th century. A full account of this transmission and transformation is found on the Aristotelian Natural Philosophy - History page.

The 16th and 17th centuries saw sustained challenge to the Aristotelian framework from multiple directions: Copernican heliocentrism undermined the two-region cosmology; Galileo's work on motion challenged the account of natural and violent motion; and the mechanical philosophy of Descartes, Gassendi, and others replaced Aristotelian matter theory with corpuscularianism. By the late 17th century, Aristotelian natural philosophy had been largely displaced in European natural science, though it retained influence in philosophy and continued to be taught in many universities into the 18th century.

There is broad consensus in the history and philosophy of science that Aristotelian natural philosophy was the dominant framework for natural inquiry in European and Islamic intellectual traditions from roughly the 3rd century BCE through the 16th century CE, and that the Scientific Revolution involved a fundamental rejection of its core cosmological and physical commitments. The History of Science Consensus page outlines the areas of agreement and the debates that remain active among historians.

Aristotle's teleology as genuine scientific explanation - Some philosophers of science argue that Aristotelian final causation represents a legitimate and irreducible mode of explanation, particularly in biology, and that its elimination from the natural sciences was a conceptual loss rather than simply a correction. See Teleology as Legitimate Explanation - Viewpoint.

Aristotelian natural philosophy as proto-science superseded - The dominant view in mainstream philosophy of science holds that Aristotelian natural philosophy, while historically significant, made empirical and structural errors that the Scientific Revolution correctly identified and replaced. See Superseded Framework - Viewpoint.

Continuity thesis - the Scientific Revolution as revision, not rupture - Some historians of science, associated with figures such as Pierre Duhem, argue that the transition from Aristotelian natural philosophy to early modern science was more gradual and continuous than the “revolution” narrative implies, with medieval scholastic natural philosophy laying essential groundwork. See Continuity Thesis - Viewpoint.

Aristotelian revival in philosophy of nature - A minority position within contemporary philosophy holds that Aristotelian categories - particularly substance, form, and the four causes - offer resources for addressing problems in philosophy of mind, biology, and metaphysics that mechanistic frameworks handle poorly. See Neo-Aristotelian Revival - Viewpoint.

• Aristotelian Natural Philosophy - History
• Aristotelian Natural Philosophy - Debate
• Aristotelian Natural Philosophy - History of Science Consensus
• Impetus Theory
• Tychonic System
• Ptolemaic Astronomy
• Copernican Heliocentrism
• Scientific Revolution
• Scholasticism
• Philosophy of Science
• Teleology

1. Aristotle, Physics, trans. R. P. Hardie and R. K. Gaye, in The Complete Works of Aristotle, ed. Jonathan Barnes (Princeton University Press, 1984).
2. Aristotle, On the Heavens (De Caelo), trans. J. L. Stocks, in Barnes, Complete Works.
3. Aristotle, On Generation and Corruption, trans. H. H. Joachim, in Barnes, Complete Works.
4. David Ross, Aristotle (Methuen, 1923; 6th ed. Routledge, 1995), ch. 6.
5. Edward Grant, A History of Natural Philosophy: From the Ancient World to the Nineteenth Century (Cambridge University Press, 2007).
6. David C. Lindberg, The Beginnings of Western Science (University of Chicago Press, 1992; 2nd ed. 2007).
7. A. C. Crombie, Robert Grosseteste and the Origins of Experimental Science (Oxford University Press, 1953) - for the continuity thesis.
8. Pierre Duhem, Le Système du monde, 10 vols. (Hermann, 1913-1959).
9. Mariska Leunissen, Explanation and Teleology in Aristotle's Science of Nature (Cambridge University Press, 2010).
10. Amos Funkenstein, Theology and the Scientific Imagination (Princeton University Press, 1986).