The
natural sciences
Natural science is one of the branches of science concerned with the description, understanding and prediction of natural phenomena, based on empirical evidence from observation and experimentation. Mechanisms such as peer review and repeatab ...
saw various advancements during the
Golden Age of Islam
The Islamic Golden Age was a period of cultural, economic, and scientific flourishing in the history of Islam, traditionally dated from the 8th century to the 14th century. This period is traditionally understood to have begun during the reign ...
(from roughly the mid 8th to the mid 13th centuries), adding a number of innovations to the
Transmission of the Classics (such as
Aristotle
Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of phil ...
,
Ptolemy
Claudius Ptolemy (; grc-gre, Πτολεμαῖος, ; la, Claudius Ptolemaeus; AD) was a mathematician, astronomer, astrologer, geographer, and music theorist, who wrote about a dozen scientific treatises, three of which were of importanc ...
,
Euclid
Euclid (; grc-gre, Wikt:Εὐκλείδης, Εὐκλείδης; BC) was an ancient Greek mathematician active as a geometer and logician. Considered the "father of geometry", he is chiefly known for the ''Euclid's Elements, Elements'' trea ...
,
Neoplatonism
Neoplatonism is a strand of Platonism, Platonic philosophy that emerged in the 3rd century AD against the background of Hellenistic philosophy and Hellenistic religion, religion. The term does not encapsulate a set of ideas as much as a chain of ...
).
[''Classical Arabic Philosophy An Anthology of Sources'', Translated by Jon McGinnis and David C. Reisman. Indianapolis: Hackett Publishing Company, 2007. pg. xix] During this period, Islamic theology was encouraging of thinkers to find knowledge. Thinkers from this period included
Al-Farabi
Abu Nasr Muhammad Al-Farabi ( fa, ابونصر محمد فارابی), ( ar, أبو نصر محمد الفارابي), known in the Western world, West as Alpharabius; (c. 872 – between 14 December, 950 and 12 January, 951)PDF version was a reno ...
,
Abu Bishr Matta,
Ibn Sina
Ibn Sina ( fa, ابن سینا; 980 – June 1037 CE), commonly known in the West as Avicenna (), was a Persian polymath who is regarded as one of the most significant physicians, astronomers, philosophers, and writers of the Islamic G ...
,
al-Hassan Ibn al-Haytham and
Ibn Bajjah
Abū Bakr Muḥammad ibn Yaḥyà ibn aṣ-Ṣā’igh at-Tūjībī ibn Bājja ( ar, أبو بكر محمد بن يحيى بن الصائغ التجيبي بن باجة), best known by his Latinised name Avempace (; – 1138), was an A ...
. These works and the important commentaries on them were the wellspring of science during the medieval period. They were
translated
Translation is the communication of the meaning of a source-language text by means of an equivalent target-language text. The English language draws a terminological distinction (which does not exist in every language) between ''transla ...
into
Arabic
Arabic (, ' ; , ' or ) is a Semitic languages, Semitic language spoken primarily across the Arab world.Semitic languages: an international handbook / edited by Stefan Weninger; in collaboration with Geoffrey Khan, Michael P. Streck, Janet C ...
, the ''
lingua franca
A lingua franca (; ; for plurals see ), also known as a bridge language, common language, trade language, auxiliary language, vehicular language, or link language, is a language systematically used to make communication possible between groups ...
'' of this period.
Islamic scholarship in the sciences had inherited
Aristotelian physics
Aristotelian physics is the form of natural science described in the works of the Greek philosopher Aristotle (384–322 BC). In his work ''Physics'', Aristotle intended to establish general principles of change that govern all natural bodies, b ...
from the Greeks and during the
Islamic Golden Age
The Islamic Golden Age was a period of cultural, economic, and scientific flourishing in the history of Islam, traditionally dated from the 8th century to the 14th century. This period is traditionally understood to have begun during the reign ...
developed it further. However the Islamic world had a greater respect for knowledge gained from empirical observation, and believed that the universe is governed by a single set of laws. Their use of empirical observation led to the formation of crude forms of the
scientific method
The scientific method is an empirical method for acquiring knowledge that has characterized the development of science since at least the 17th century (with notable practitioners in previous centuries; see the article history of scientific m ...
.
The study of physics in the Islamic world started in
Iraq
Iraq,; ku, عێراق, translit=Êraq officially the Republic of Iraq, '; ku, کۆماری عێراق, translit=Komarî Êraq is a country in Western Asia. It is bordered by Turkey to Iraq–Turkey border, the north, Iran to Iran–Iraq ...
and
Egypt
Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia via a land bridge formed by the Sinai Peninsula. It is bordered by the Mediter ...
.
Fields of physics studied in this period include
optics
Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultraviole ...
,
mechanics
Mechanics (from Ancient Greek: μηχανική, ''mēkhanikḗ'', "of machines") is the area of mathematics and physics concerned with the relationships between force, matter, and motion among physical objects. Forces applied to objects r ...
(including
statics
Statics is the branch of classical mechanics that is concerned with the analysis of force and torque (also called moment) acting on physical systems that do not experience an acceleration (''a''=0), but rather, are in static equilibrium with ...
,
dynamics,
kinematics
Kinematics is a subfield of physics, developed in classical mechanics, that describes the Motion (physics), motion of points, Physical object, bodies (objects), and systems of bodies (groups of objects) without considering the forces that cause ...
and
motion
In physics, motion is the phenomenon in which an object changes its position with respect to time. Motion is mathematically described in terms of displacement, distance, velocity, acceleration, speed and frame of reference to an observer and mea ...
), and
astronomy
Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest ...
.
Physics
Islamic scholarship had inherited
Aristotelian physics
Aristotelian physics is the form of natural science described in the works of the Greek philosopher Aristotle (384–322 BC). In his work ''Physics'', Aristotle intended to establish general principles of change that govern all natural bodies, b ...
from the Greeks and during the
Islamic Golden Age
The Islamic Golden Age was a period of cultural, economic, and scientific flourishing in the history of Islam, traditionally dated from the 8th century to the 14th century. This period is traditionally understood to have begun during the reign ...
developed it further, especially placing emphasis on observation and ''
a priori
("from the earlier") and ("from the later") are Latin phrases used in philosophy to distinguish types of knowledge, justification, or argument by their reliance on empirical evidence or experience. knowledge is independent from current ...
'' reasoning, developing early forms of the
scientific method
The scientific method is an empirical method for acquiring knowledge that has characterized the development of science since at least the 17th century (with notable practitioners in previous centuries; see the article history of scientific m ...
. With
Aristotelian physics
Aristotelian physics is the form of natural science described in the works of the Greek philosopher Aristotle (384–322 BC). In his work ''Physics'', Aristotle intended to establish general principles of change that govern all natural bodies, b ...
, physics was seen as lower than demonstrative mathematical sciences, but in terms of a larger theory of knowledge, physics was higher than astronomy; many of whose principles derive from physics and metaphysics.
[. ''Islam, Science, and the Challenge of History''. New Haven:Yale University Press. pg 57] The primary subject of physics, according to
Aristotle
Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of phil ...
, was motion or change; there were three factors involved with this change, underlying thing, privation, and form. In his ''Metaphysics'',
Aristotle
Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of phil ...
believed that the ''Unmoved Mover'' was responsible for the movement of the cosmos, which
Neoplatonists
Neoplatonism is a strand of Platonic philosophy that emerged in the 3rd century AD against the background of Hellenistic philosophy and religion. The term does not encapsulate a set of ideas as much as a chain of thinkers. But there are some ide ...
later generalized as the cosmos were eternal.
Al-Kindi
Abū Yūsuf Yaʻqūb ibn ʼIsḥāq aṣ-Ṣabbāḥ al-Kindī (; ar, أبو يوسف يعقوب بن إسحاق الصبّاح الكندي; la, Alkindus; c. 801–873 AD) was an Arab Muslim philosopher, polymath, mathematician, physician ...
argued against the idea of the cosmos being eternal by claiming that the eternality of the world lands one in a different sort of absurdity involving the infinite;
Al-Kindi
Abū Yūsuf Yaʻqūb ibn ʼIsḥāq aṣ-Ṣabbāḥ al-Kindī (; ar, أبو يوسف يعقوب بن إسحاق الصبّاح الكندي; la, Alkindus; c. 801–873 AD) was an Arab Muslim philosopher, polymath, mathematician, physician ...
asserted that the cosmos must have a temporal origin because traversing an infinite was impossible.
One of the first commentaries of
Aristotle's ''Metaphysics'' is by
Al-Farabi
Abu Nasr Muhammad Al-Farabi ( fa, ابونصر محمد فارابی), ( ar, أبو نصر محمد الفارابي), known in the Western world, West as Alpharabius; (c. 872 – between 14 December, 950 and 12 January, 951)PDF version was a reno ...
. In "'The Aims of
Aristotle's Metaphysics",
Al-Farabi
Abu Nasr Muhammad Al-Farabi ( fa, ابونصر محمد فارابی), ( ar, أبو نصر محمد الفارابي), known in the Western world, West as Alpharabius; (c. 872 – between 14 December, 950 and 12 January, 951)PDF version was a reno ...
argues that metaphysics is not specific to natural beings, but at the same time, metaphysics is higher in universality than natural beings.
Optics
![Book of Optics Cover Page](https://upload.wikimedia.org/wikipedia/commons/4/45/Book_of_Optics_Cover_Page.jpg)
One field in physics,
optics
Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultraviole ...
, developed rapidly in this period. By the ninth century, there were works on physiological optics as well as mirror reflections, and geometrical and physical optics.
[ Dallal, Ahmad. ''Islam, Science, and the Challenge of History''. New Haven: Yale University Press, 2010. pg. 38] In the eleventh century,
Ibn al-Haytham
Ḥasan Ibn al-Haytham, Latinized as Alhazen (; full name ; ), was a medieval mathematician, astronomer, and physicist of the Islamic Golden Age from present-day Iraq.For the description of his main fields, see e.g. ("He is one of the prin ...
not only rejected the Greek idea about vision, he came up with a new theory.
Ibn Sahl (c. 940-1000), a mathematician and physicist connected with the court of
Baghdad
Baghdad (; ar, بَغْدَاد , ) is the capital of Iraq and the second-largest city in the Arab world after Cairo. It is located on the Tigris near the ruins of the ancient city of Babylon and the Sassanid Persian capital of Ctesiphon ...
, wrote a treatise ''On Burning Mirrors and Lenses'' in 984 in which he set out his understanding of how
curved mirror
A curved mirror is a mirror with a curved reflecting surface. The surface may be either ''convex'' (bulging outward) or ''concave'' (recessed inward). Most curved mirrors have surfaces that are shaped like part of a sphere, but other shapes are ...
s and
lens
A lens is a transmissive optical device which focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements''), ...
es bend and focus
light
Light or visible light is electromagnetic radiation that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 tera ...
. Ibn Sahl is credited with discovering the law of
refraction
In physics, refraction is the redirection of a wave as it passes from one medium to another. The redirection can be caused by the wave's change in speed or by a change in the medium. Refraction of light is the most commonly observed phenomeno ...
, now usually called
Snell's law
Snell's law (also known as Snell–Descartes law and ibn-Sahl law and the law of refraction) is a formula used to describe the relationship between the angles of incidence and refraction, when referring to light or other waves passing through ...
.
[R. Rashed, "A pioneer in anaclastics: Ibn Sahl on burning mirrors and lenses", '']Isis
Isis (; ''Ēse''; ; Meroitic: ''Wos'' 'a''or ''Wusa''; Phoenician: 𐤀𐤎, romanized: ʾs) was a major goddess in ancient Egyptian religion whose worship spread throughout the Greco-Roman world. Isis was first mentioned in the Old Kingd ...
'' 81, p. 464–491, 1990. He used this law to work out the shapes of lenses that focus light with no geometric aberrations, known as
anaclastic lenses.
Ibn al-Haytham
Ḥasan Ibn al-Haytham, Latinized as Alhazen (; full name ; ), was a medieval mathematician, astronomer, and physicist of the Islamic Golden Age from present-day Iraq.For the description of his main fields, see e.g. ("He is one of the prin ...
(known in
Western Europe
Western Europe is the western region of Europe. The region's countries and territories vary depending on context.
The concept of "the West" appeared in Europe in juxtaposition to "the East" and originally applied to the ancient Mediterranean ...
as ''Alhacen'' or ''Alhazen'') (
965-
1040
Year 1040 ( MXL) was a leap year starting on Tuesday (link will display the full calendar) of the Julian calendar.
Events
By place Europe
* Spring – Nikephoros Dokeianos, Byzantine governor of the Catepanate of Italy, is murdered ...
), often regarded as the "father of optics"
[R. L. Verma, "Al-Hazen: father of modern optics", ''Al-Arabi'', 8 (1969): 12-13] and a pioneer of the
scientific method
The scientific method is an empirical method for acquiring knowledge that has characterized the development of science since at least the 17th century (with notable practitioners in previous centuries; see the article history of scientific m ...
, formulated "the first comprehensive and systematic alternative to Greek optical theories."
[D. C. Lindberg, "Alhazen's Theory of Vision and its Reception in the West", ''Isis'', 58 (1967), p. 322.] He postulated in his "Book of Optics" that light was reflected upon different surfaces in different directions, thus causing different light signatures for a certain object that we see.
It was a different approach than that which was previously thought by Greek scientists, such as
Euclid
Euclid (; grc-gre, Wikt:Εὐκλείδης, Εὐκλείδης; BC) was an ancient Greek mathematician active as a geometer and logician. Considered the "father of geometry", he is chiefly known for the ''Euclid's Elements, Elements'' trea ...
or
Ptolemy
Claudius Ptolemy (; grc-gre, Πτολεμαῖος, ; la, Claudius Ptolemaeus; AD) was a mathematician, astronomer, astrologer, geographer, and music theorist, who wrote about a dozen scientific treatises, three of which were of importanc ...
, who believed rays were
emitted from the eye to an object and back again. Al-Haytham, with this new theory of
optics
Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultraviole ...
, was able to study the geometric aspects of the visual cone theories without explaining the physiology of perception.
Also in his Book of Optics, Ibn al-Haytham used mechanics to try and understand optics. Using projectiles, he observed that objects that hit a target perpendicularly exert much more force than projectiles that hit at an angle. Al-Haytham applied this discovery to optics and tried to explain why direct light hurts the eye, because direct light approaches perpendicularly and not at an oblique angle.
He developed a
camera obscura
A camera obscura (; ) is a darkened room with a aperture, small hole or lens at one side through which an image is 3D projection, projected onto a wall or table opposite the hole.
''Camera obscura'' can also refer to analogous constructions su ...
to demonstrate that light and color from different candles can be passed through a single aperture in straight lines, without intermingling at the aperture. His theories were transmitted to the West.
[ His work influenced ]Roger Bacon
Roger Bacon (; la, Rogerus or ', also '' Rogerus''; ), also known by the scholastic accolade ''Doctor Mirabilis'', was a medieval English philosopher and Franciscan friar who placed considerable emphasis on the study of nature through empiri ...
, John Peckham
John Peckham (c. 1230 – 8 December 1292) was Archbishop of Canterbury in the years 1279–1292. He was a native of Sussex who was educated at Lewes Priory and became a Friar Minor about 1250. He studied at the University of Paris under B ...
and Vitello
Vitello ( pl, Witelon; german: Witelo; – 1280/1314) was a friar, theologian, natural philosopher and an important figure in the history of philosophy in Poland.
Name
Vitello's name varies with some sources. In earlier publications he was quo ...
, who built upon his work and ultimately transmitted it to Kepler
Johannes Kepler (; ; 27 December 1571 – 15 November 1630) was a German astronomer, mathematician, astrologer, natural philosopher and writer on music. He is a key figure in the 17th-century Scientific Revolution, best known for his laws o ...
.[
Taqī al-Dīn tried to disprove the widely held belief that light is emitted by the eye and not the object that is being observed. He explained that, if light came from our eyes at a constant velocity it would take much too long to illuminate the stars for us to see them while we are still looking at them, because they are so far away. Therefore, the illumination must be coming from the stars so we can see them as soon as we open our eyes.
]
Astronomy
The Islamic understanding of the astronomical model was based on the Greek Ptolemaic system. However, many early astronomers had started to question the model. It was not always accurate in its predictions and was over complicated because astronomers were trying to mathematically describe the movement of the heavenly bodies. Ibn al-Haytham
Ḥasan Ibn al-Haytham, Latinized as Alhazen (; full name ; ), was a medieval mathematician, astronomer, and physicist of the Islamic Golden Age from present-day Iraq.For the description of his main fields, see e.g. ("He is one of the prin ...
published ''Al-Shukuk ala Batiamyus'' ("Doubts on Ptolemy"), which outlined his many criticisms of the Ptolemaic paradigm. This book encouraged other astronomers to develop new models to explain celestial movement better than Ptolemy. In al-Haytham's ''Book of Optics
The ''Book of Optics'' ( ar, كتاب المناظر, Kitāb al-Manāẓir; la, De Aspectibus or ''Perspectiva''; it, Deli Aspecti) is a seven-volume treatise on optics and other fields of study composed by the medieval Arab scholar Ibn al- ...
'' he argues that the celestial spheres were not made of solid matter, and that the heavens are less dense that air.[Rosen, Edward. (1985). "The Dissolution of the Solid Celestial Spheres". ''Journal of the History of Ideas''. Vol 46(1):13-31.] Al-Haytham eventually concludes that heavenly bodies follow the same laws of physics as earthly bodies.[Duhem, Pierre. (1969). "To Save the Phenomena: An Essay on the Idea of Physical Theory from Plato to Galileo". University of Chicago Press, Chicago.] Some astronomers theorized about gravity too, al-Khazini
Abū al-Fath Abd al-Rahman Mansūr al-Khāzini or simply al-Khāzini (, flourished 1115–1130) was an Iranian astronomer of Greek origin from Seljuk Persia. His astronomical tables written under the patronage of Sultan Sanjar (', 1115) is co ...
suggests that the gravity an object contains varies depending on its distance from the center of the universe. The center of the universe in this case refers to the center of the Earth.
Mechanics
Impetus
John Philoponus
John Philoponus (Greek: ; ; c. 490 – c. 570), also known as John the Grammarian or John of Alexandria, was a Byzantine Greek philologist, Aristotelian commentator, Christian theologian and an author of a considerable number of philosophical tre ...
had rejected the Aristotelian view of motion, and argued that an object acquires an inclination to move when it has a motive power impressed on it. In the eleventh century Ibn Sina
Ibn Sina ( fa, ابن سینا; 980 – June 1037 CE), commonly known in the West as Avicenna (), was a Persian polymath who is regarded as one of the most significant physicians, astronomers, philosophers, and writers of the Islamic G ...
had roughly adopted this idea, believing that a moving object has force which is dissipated by external agents like air resistance.[Sayili, Aydin. "Ibn Sina and Buridan on the Motion the Projectile". Annals of the New York Academy of Sciences vol. 500(1). p.477-482.]
Ibn Sina made distinction between 'force' and 'inclination' (called "''mayl''"), he claimed that an object gained ''mayl'' when the object is in opposition to its natural motion. So he concluded that continuation of motion is attributed to the inclination that is transferred to the object, and that object will be in motion until the ''mayl'' is spent. He also claimed that projectile in a vacuum would not stop unless it is acted upon. This conception of motion is consistent with Newton's first law of motion, inertia, which states that an object in motion will stay in motion unless it is acted on by an external force.[Espinoza, Fernando. "An Analysis of the Historical Development of Ideas About Motion and its Implications for Teaching". Physics Education. Vol. 40(2).] This idea which dissented from the Aristotelian view was basically abandoned until it was described as "impetus" by John Buridan
Jean Buridan (; Latin: ''Johannes Buridanus''; – ) was an influential 14th-century French philosopher.
Buridan was a teacher in the faculty of arts at the University of Paris for his entire career who focused in particular on logic and the wo ...
, who may have been influenced by Ibn Sina.
Acceleration
In Abū Rayḥān al-Bīrūnī text ''Shadows'', he recognizes that non-uniform motion is the result of acceleration. Ibn-Sina's theory of mayl tried to relate the velocity and weight of a moving object, this idea closely resembled the concept of momentum[Nasr S.H., Razavi M.A.. "The islamic Intellectual Tradition in Persia" (1996). Routledge] Aristotle's theory of motion stated that a constant force produces a uniform motion, Abu'l-Barakāt al-Baghdādī
Abu'l-Barakāt Hibat Allah ibn Malkā al-Baghdādī ( ar, أبو البركات هبة الله بن ملكا البغدادي; c. 1080 – 1164 or 1165 CE) was an Islamic philosopher, physician and physicist of Jewish descent from Baghdad, Iraq. ...
contradicted this and developed his own theory of motion. In his theory he showed that velocity and acceleration are two different things and force is proportional to acceleration and not velocity.
Reaction
Ibn Bajjah
Abū Bakr Muḥammad ibn Yaḥyà ibn aṣ-Ṣā’igh at-Tūjībī ibn Bājja ( ar, أبو بكر محمد بن يحيى بن الصائغ التجيبي بن باجة), best known by his Latinised name Avempace (; – 1138), was an A ...
proposed that for every force there is always a reaction force. While he did not specify that these forces need be equal; it is still an early version of the third law of motion which states that for every action there is an equal and opposite reaction.[Franco, Abel B.. "Avempace, Projectile Motion, and Impetus Theory". ''Journal of the History of Ideas''. Vol. 64(4): 543.]
See also
* Astronomy in the medieval Islamic world
*History of optics
Optics began with the development of lenses by the ancient Egyptians and Mesopotamians, followed by theories on light and vision developed by ancient Greek philosophers, and the development of geometrical optics in the Greco-Roman world. The w ...
*History of physics
Physics is a branch of science whose primary objects of study are matter and energy. Discoveries of physics find applications throughout the natural sciences and in technology. Physics today may be divided loosely into classical physics and mode ...
*History of scientific method
The history of scientific method considers changes in the methodology of scientific inquiry, as distinct from the history of science itself. The development of rules for scientific reasoning has not been straightforward; scientific method has been ...
*Islamic world contributions to Medieval Europe
During the High Middle Ages, the Islamic world was at its cultural peak, supplying information and ideas to Europe, via Al-Andalus, Sicily and the Crusader kingdoms in the Levant. These included Latin translations of the Greek Classics and of ...
*Islamic Golden Age
The Islamic Golden Age was a period of cultural, economic, and scientific flourishing in the history of Islam, traditionally dated from the 8th century to the 14th century. This period is traditionally understood to have begun during the reign ...
*Science in the medieval Islamic world
Science in the medieval Islamic world was the science developed and practised during the Islamic Golden Age under the Umayyads of Córdoba, the Abbadids of Seville, the Samanids, the Ziyarids, the Buyids in Persia, the Abbasid Caliphate and ...
*Science in the Middle Ages
The history of science covers the development of science from ancient times to the present. It encompasses all three major branches of science: natural, social, and formal.
Science's earliest roots can be traced to Ancient Egypt and Meso ...
References
{{DEFAULTSORT:Physics In Medieval Islam
Science in the medieval Islamic world
History of physics
Islamic Golden Age