|Part of a series on the|
|Logic ( Organon )|
|Natural philosophy (physics)|
[*]: Generally agreed to be spurious[†]: Authenticity disputed
On the Heavens (Greek: Περὶ οὐρανοῦ; Latin: De Caelo or De Caelo et Mundo) is Aristotle's chief cosmological treatise: written in 350 BC it contains his astronomical theory and his ideas on the concrete workings of the terrestrial world. It should not be confused with the spurious work On the Universe (De mundo, also known as On the Cosmos).
According to Aristotle in On the Heavens, the heavenly bodies are the most perfect realities, (or "substances"), whose motions are ruled by principles other than those of bodies in the sublunary sphere. The latter are composed of one or all of the four classical elements (earth, water, air, fire) and are perishable; but the matter of which the heavens are made is imperishable aether, so they are not subject to generation and corruption. Hence their motions are eternal and perfect, and the perfect motion is the circular one, which, unlike the earthly up-and down-ward locomotions, can last eternally selfsame - an early predecessor to Newton's First Law of Motion. Aristotle theorized that aether did not exist anywhere on Earth, but that it was an element exclusive to the heavens. As substances, celestial bodies have matter (aether) and form (a given period of uniform rotation). Sometimes Aristotle seems to regard them as living beings with a rational soul as their form(see also Metaphysics , bk. XII).
Aristotle proposed a geocentric model of the universe in On the Heavens. The Earth is the center of motion of the universe, with circular motion being perfect because Earth was at the center of it. There can only be one center of the universe, and as a result there are no other inhabited worlds within it besides Earth. As such the Earth is unique and alone in this regard. Aristotle theorized that beyond the sublunary sphere and the heavens is an external spiritual space that mankind cannot fathom directly. This work is significant as one of the defining pillars of the Aristotelian worldview, a school of philosophy that dominated intellectual thinking for almost two millennia. Similarly, this work and others by Aristotle were important seminal works by which much of scholasticism was derived.
Aristotelian philosophy and cosmology was influential in the Islamic world, where his ideas were taken up by the Falsafa school of philosophy throughout the later half of the first millennia AD. Of these, philosophers Averroes and Avicenna are especially notable. Averroes in particular wrote extensively about On The Heavens, trying for some time to reconcile the various themes of Aristotelian philosophy, such as natural movement of the elements and the concept of planetary spheres centered on the Earth, with the mathematics of Ptolemy.These ideas would remain central to philosophical thought in the Islamic world well into the pre-modern period, and its influences can be found in both the theological and mystical tradition, including in the writings of al-Ghazali and Fakhr al-Din al-Razi.
European philosophers had a similarly complex relationship with De Caelo, attempting to reconcile church doctrine with the mathematics of Ptolemy and the structure of Aristotle. A particularly cogent example of this is in the work of Thomas Aquinas, theologian, philosopher and writer of the 13th century. Known today as St. Thomas of the Catholic Church, Aquinas worked to synthesize Aristotle's cosmology as presented in De Caelo with Christian doctrine, an endeavor that led him to reclassify Aristotle's unmoved movers as angels and attributing the 'first cause' of motion in the celestial spheres to them.Otherwise, Aquinas accepted Aristotle's explanation of the physical world, including his cosmology and physics.
The 14th century French philosopher Nicole Oresme translated and commentated on De Caelo in his role as adviser to King Charles V of France, on two separate occasions, once early on in life, and again near the end of it. These versions were a traditional Latin transcription and a more comprehensive French version that synthesized his views on cosmological philosophy in its entirety, Questiones Super de Celo and Livre du ciel et du monde respectively. "Livre du ciel et du monde" was written at the command of King Charles V, though for what purpose remains of some debate. Some speculate that, having already had Oresme translate Aristotelian works on ethics and politics in the hope of educating his courtiers, doing the same with De Caelo may be of some value to the king.
(In reverse chronological order)
The cosmos is the Universe. Using the word cosmos rather than the word universe implies viewing the universe as a complex and orderly system or entity; the opposite of chaos. The cosmos, and our understanding of the reasons for its existence and significance, are studied in cosmology – a very broad discipline covering any scientific, religious, or philosophical contemplation of the cosmos and its nature, or reasons for existing. Religious and philosophical approaches may include in their concepts of the cosmos various spiritual entities or other matters deemed to exist outside our physical universe.
In astronomy and navigation, the celestial sphere is an abstract sphere that has an arbitrarily large radius and is concentric to Earth. All objects in the sky can be conceived as being projected upon the inner surface of the celestial sphere, which may be centered on Earth or the observer. If centered on the observer, half of the sphere would resemble a hemispherical screen over the observing location.
Albert Brudzewski, alsoAlbert Blar , Albert of Brudzewo or Wojciech Brudzewski was a Polish astronomer, mathematician, philosopher and diplomat.
In astronomy, the geocentric model is a superseded description of the Universe with Earth at the center. Under the geocentric model, the Sun, Moon, stars, and planets all orbit Earth. The geocentric model was the predominant description of the cosmos in many ancient civilizations, such as those of Aristotle in Classical Greece and Ptolemy in Roman Egypt.
Aristotelian theology and the scholastic view of God have been influential in Western intellectual history.
The cosmological model of concentricspheres, developed by Eudoxus, Callippus, and Aristotle, employed celestial spheres all centered on the Earth. In this respect, it differed from the epicyclic and eccentric models with multiple centers, which were used by Ptolemy and other mathematical astronomers until the time of Copernicus.
Aristotelianism is a philosophical tradition inspired by the work of Aristotle, usually characterized by deductive logic and an analytic inductive method in the study of nature and natural law. It answers why-questions by a scheme of four causes, including purpose or teleology, and emphasizes virtue ethics. Aristotle and his school wrote tractates on physics, biology, metaphysics, logic, ethics, aesthetics, poetry, theatre, music, rhetoric, psychology, linguistics, economics, politics, and government. Any school of thought that takes one of Aristotle's distinctive positions as its starting point can be considered "Aristotelian" in the widest sense. This means that different Aristotelian theories may not have much in common as far as their actual content is concerned besides their shared reference to Aristotle.
The celestial spheres, or celestial orbs, were the fundamental entities of the cosmological models developed by Plato, Eudoxus, Aristotle, Ptolemy, Copernicus, and others. In these celestial models, the apparent motions of the fixed stars and planets are accounted for by treating them as embedded in rotating spheres made of an aetherial, transparent fifth element (quintessence), like jewels set in orbs. Since it was believed that the fixed stars did not change their positions relative to one another, it was argued that they must be on the surface of a single starry sphere.
Nicole Oresme, also known as Nicolas Oresme, Nicholas Oresme, or Nicolas d'Oresme, was a significant philosopher of the later Middle Ages. He wrote influential works on economics, mathematics, physics, astrology and astronomy, philosophy, and theology; was Bishop of Lisieux, a translator, a counselor of King Charles V of France, and one of the most original thinkers of 14th-century Europe.
The fixed stars compose the background of astronomical objects that appear not to move relative to each other in the night sky compared to the foreground of Solar System objects that do. Generally, the fixed stars are taken to include all stars other than the Sun. Nebulae and other deep-sky objects may also be counted among the fixed stars.
According to ancient and medieval science, aether, also spelled æther, aither, or ether and also called quintessence, is the material that fills the region of the universe above the terrestrial sphere. The concept of aether was used in several theories to explain several natural phenomena, such as the traveling of light and gravity. In the late 19th century, physicists postulated that aether permeated all throughout space, providing a medium through which light could travel in a vacuum, but evidence for the presence of such a medium was not found in the Michelson–Morley experiment, and this result has been interpreted as meaning that no such luminiferous aether exists.
In Aristotelian physics and Greek astronomy, the sublunary sphere is the region of the geocentric cosmos below the Moon, consisting of the four classical elements: earth, water, air, and fire.
The unmoved mover or prime mover is a concept advanced by Aristotle as a primary cause or "mover" of all the motion in the universe. As is implicit in the name, the unmoved mover moves other things, but is not itself moved by any prior action. In Book 12 of his Metaphysics, Aristotle describes the unmoved mover as being perfectly beautiful, indivisible, and contemplating only the perfect contemplation: self-contemplation. He equates this concept also with the active intellect. This Aristotelian concept had its roots in cosmological speculations of the earliest Greek pre-Socratic philosophers and became highly influential and widely drawn upon in medieval philosophy and theology. St. Thomas Aquinas, for example, elaborated on the unmoved mover in the Quinque viae.
Greek astronomy is astronomy written in the Greek language in classical antiquity. Greek astronomy is understood to include the ancient Greek, Hellenistic, Greco-Roman, and Late Antiquity eras. It is not limited geographically to Greece or to ethnic Greeks, as the Greek language had become the language of scholarship throughout the Hellenistic world following the conquests of Alexander. This phase of Greek astronomy is also known as Hellenistic astronomy, while the pre-Hellenistic phase is known as Classical Greek astronomy. During the Hellenistic and Roman periods, much of the Greek and non-Greek astronomers working in the Greek tradition studied at the Musaeum and the Library of Alexandria in Ptolemaic Egypt.
Islamic cosmology is the cosmology of Islamic societies. It is mainly derived from the Qur'an, Hadith, Sunnah, and current Islamic as well as other pre-Islamic sources. The Qur'an itself mentions seven heavens.
Aristotelian physics is the form of natural science described in the works of the Greek philosopher Aristotle. In his work Physics, Aristotle intended to establish general principles of change that govern all natural bodies, both living and inanimate, celestial and terrestrial – including all motion, quantitative change, qualitative change, and substantial change. To Aristotle, 'physics' was a broad field that included subjects that would now be called the philosophy of mind, sensory experience, memory, anatomy and biology. It constitutes the foundation of the thought underlying many of his works.
The theory of impetus was an auxiliary or secondary theory of Aristotelian dynamics, put forth initially to explain projectile motion against gravity. It was introduced by John Philoponus in the 6th century, and elaborated by Nur ad-Din al-Bitruji at the end of the 12th century. The theory was modified by Avicenna in the 11th century and Hibat Allah Abu'l-Barakat al-Baghdaadi in the 12th century, before it was later established in Western scientific thought by Jean Buridan in the 14th century. It is the intellectual precursor to the concepts of inertia, momentum and acceleration in classical mechanics.
Ancient, medieval and Renaissance astronomers and philosophers developed many different theories about the dynamics of the celestial spheres. They explained the motions of the various nested spheres in terms of the materials of which they were made, external movers such as celestial intelligences, and internal movers such as motive souls or impressed forces. Most of these models were qualitative, although a few of them incorporated quantitative analyses that related speed, motive force and resistance.
The eternity of the world is the question of whether the world has a beginning in time or has existed from eternity. It was a concern for both ancient philosophers and the medieval theologians and medieval philosophers of the 13th century. The problem became a focus of a dispute in the 13th century, when some of the works of Aristotle, who believed in the eternity of the world, were rediscovered in the Latin West. This view conflicted with the view of the Catholic Church that the world had a beginning in time. The Aristotelian view was prohibited in the Condemnations of 1210–1277.
Jacques du Chevreul (1595-1649). Jacques du Chevreul was born in Coutances, France and died in Paris, France. Du Chevreul grew up in an educated household and was the son of a magistrate. In 1616, he received a Master of Arts for studying humanities and philosophy at the University of Paris. Du Chevreul continued education at a higher level and received a Bachelor of Divinity for theology in 1619. He did not start teaching until 1620 where he remained associated with College Harcourt and University of Paris, up until two years before his death when he taught philosophy at the College Royal. Throughout his lifetime Jacques du Chevreul held various teaching and administrative positions including principal and rector. Little is known about his later life. Although he studied subjects such as philosophy, logic, ethics, metaphysics, and physics, he published his two popular books on mathematics. Arithmetica (1622) and Sphaera were both published in Paris, France. Sphaera, du Chevreul's most popular book was about his view of the world and the universe. He used references from the Bible, Aristotle, and Plato to reject the Copernican model and instead created his own eccentric-epicycle geocentric model of the universe. Du Chevreul believed that the earth was the center of the universe, but that the major planets Venus and Mercury orbited around the sun. He theorized that there were wandering and fixed stars in the heavens and there were a total of thirteen planets in his model. The heavens were in the order of the Moon, the Sun, Mars, Jupiter surrounded by four Medicean stars, Saturn with two satellites, and above all these levels resided God. Du Chevreul's cosmic scheme is a highly original attempt to resist Copernicanism and accommodate Galieleo's telescopic discoveries in an Aristotelian cosmos.
|Wikimedia Commons has media related to Heavens (Aristotle) .|
|Greek Wikisource has original text related to this article:|