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Thursday, December 2, 2021

History of music

From Wikipedia, the free encyclopedia
 
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The history of music covers the historical development and presence of music from prehistoric times to present day. Though definitions of music vary wildly throughout the world, every known culture partakes in it, and music is thus considered a cultural universal. The origins of music remain highly contentious; commentators often relate it to the origin of language, with much disagreement surrounding whether music arose before, after or simultaneously with language. Many other theories exist, having been proposed by scholars from a wide range of disciplines, though none have achieved wide approval. Most cultures have their own mythical origins concerning the invention of music, generally rooted in their respective mythological, religious or philosophical beliefs.

The music of prehistoric cultures is first firmly dated to c. 40,000 BP of the Upper Paleolithic by evidence of bone flutes, though it remains unclear whether or not the actual origins lie in the earlier Middle Paleolithic period (300,000 to 50,000 BP). There is little known about prehistoric music, with traces mainly limited to iconographical evidence, as well as some simple flutes and percussion instruments. However, such evidence indicates that music existed to some extent in prehistoric societies such as the Xia dynasty and the Indus Valley Civilisation. Upon the development of writing, the music of literate civilizations—ancient music—was present in the major Chinese, Egyptian, Greek, Indian, Persian, Mesopotamian and Middle Eastern societies. It is difficult to make many generalizations about ancient music as a whole, but from what is known it was often characterized by monophony and improvisation. In ancient song forms, the texts were closely aligned with music, and though the oldest extant musical notation survives from this period, many texts survive without their accompanying music, such as the Rigveda and the Shijing Classic of Poetry. The eventual emergence of the Silk Road and increasing contact between cultures led to the transmission and exchange of musical ideas, practices and instruments.

Historically, religions have often been catalysts for music. The Vedas of Hinduism immensely influenced Indian classical music, while the Five Classics of Confucianism laid the basis for subsequent Chinese music. Following the rapid spread of Islam in the 6th century, Islamic music dominated Persia and the Arab world, and the Islamic Golden Age saw the presence of numerous important music theorists. Music written for and by the early Christian Church properly inaugurates the Western classical music tradition, which continues into medieval music where polyphony, staff notation and nascent forms of many modern instruments developed. In addition to religion, or the lack thereof, a society's music is influenced by all other aspects of its culture, including social and economic organization and experience, climate and access to technology. Many cultures have coupled music with other art forms, such as the Chinese four arts and the medieval quadrivium. The emotions and ideas that music expresses, the situations in which music is played and listened to, and the attitudes toward musicians and composers all vary between regions and periods. Many cultures have or continue to distinguish between art music (or 'classical music'), folk music and more recently, popular music.

Origins

"But that music is a language by whose means messages are elaborated, that such messages can be understood by the many but sent out only by the few, and that it alone among all language unites the contradictory character of being at once intelligible and untranslatable—these facts make the creator of music a being like the gods and make music itself the supreme mystery of human knowledge."

Claude Lévi-Strauss, The Raw and the Cooked

It remains debated as to what extent the origin of human cognition—and thus music—will ever be understood, with scholars often taking polarizing positions. The origin of music is regularly discussed as intrinsically linked with the origin of language, with the nature of their connection being a subject of serious debate. However, before the mid-late 20th century, both topics were seldom given substantial attention by scholars. Since recent resurgence in the topic, the principal source of contention is whether music began as a type of proto-language and a product of adaptation that led to language, if music is a spandrel (a phenotypic byproduct of evolution) that was the result of language or if music and language derived from a common antecedent. A well known take on the second is from cognitive psychologist and linguist Steven Pinker; in his How the Mind Works (1997), Pinker famously termed music as merely "auditory cheesecake", an analogy relating to his view of music as a spandrel, arguing that "as far as biological cause and effect is concerned, music is useless", and that "it is a technology, not an adaptation". Music psychologist Sandra Trehub notes that, like Pinker, "much of the larger scientific community is highly skeptical about links between music and biology", in opposition to specialists on the subjects. Scholars such as Joseph Carroll and Anna K. Tirovolas have rejected Pinker's take, citing evolutionary advantages including its use as practice for cognitive flexibility and "indicating to potential mates [one's] cognitive and physical flexibility and fitness".

There is little consensus on any particular theory for the origin of music, which have included contributions from archaeologists, cognitive scientists, ethnomusicologists, evolutionary biologists, linguists, neuroscientists, paleoanthropologists, philosophers and psychologists (developmental and social). Theories on the topic can be differentiated in two ways: structural models, which see music as an outgrowth of preexisting abilities, and functional models which consider its emergence as an adaptive technique. Taking the latter approach is perhaps the first significant theory on the origins of music: Charles Darwin's 1871 book The Descent of Man, and Selection in Relation to Sex, where he briefly proposed that music was originally an elaborate form of sexual selection, perhaps arising in mating calls. His theory is difficult to affirm, as there is no evidence that either sex is "more musical" thus no evidence of sexual dimorphism; there are currently no other examples of sexual selection that do not include considerable sexual dimorphism. However, citing music's use in other animals's mating systems, commentators such as Peter J.B. Slater, Katy Payne, Björn Merker, Geoffrey Miller and Peter Todd have promoted developed versions of Darwin's theory. Other theories suggest that music was developed to assist in "coordination, cohesion and cooperation", or as part of parental care, where parents use music to increase communication with—and thus the survivability of—their children. Some commentators propose music arose alongside language, both of which supposably descend from a "shared precursor", which the composer Richard Wagner termed "speech-music".

Many cultures have their own mythical origins on the creation of music. In Chinese mythology, there are various stories, the most prominent being from the Lüshi Chunqiu which says in 2697 BCE, the musician Ling Lun—on the orders of the Yellow Emperor (Huangdi)—invented bamboo flute by imitating the song of the mythical fenghuang birds. The invention of music in Ancient Greek mythology is credited to the muses, various goddesses who were daughters of the King of the gods, Zeus; Apollo, Dionysus and Orpheus were also important musical figures for the Ancient Greeks. Persian/Iranian mythology holds that Jamshid, a legendary Shah, invented music. In Christian mythology, Jubal is called "the father of all those who play the lyre and the pipe" in Genesis 4:21, and may thus be identifiable as an originator of music for Christians. Saraswati is the god of music in Hinduism, while Väinämöinen holds a similar status as an early musical figure in Finnish folklore.

Prehistoric music

Top, the purported Divje Babe Flute from Divje Babe, Slovenia; middle, a Aurignacian bone flute from Geissenklösterle, Germany; bottom, a gudi bone flute in the modern-day Jiahu, Wuyang, Henan Province.

In the broadest sense, prehistoric music—more commonly termed primitive music in the past—encompasses all music produced in preliterate cultures (prehistory), beginning at least 6 million years ago when humans and chimpanzees last had a common ancestor. Music first arose in the Paleolithic period, though it remains unclear as to whether this was the Middle (300,000 to 50,000 BP) or Upper Paleolithic (50,000 to 12,000 BP). The vast majority of Paleolithic instruments have been found in Europe and date to the Upper Paleolithic. It is certainly possible that singing emerged far before this time, though this is essentially impossible to confirm. The potentially oldest instrument is the Divje Babe Flute from the Divje Babe cave in Slovenia, dated to 43,000 and 82,000 and made from a young cave bear femur. Purportedly used by Neanderthals, the Divje Babe Flute has received extensive scholarly attention, and whether it is truly a musical instrument or an object formed by animals is the subject of intense debate. If the former, it would be the oldest known musical instrument and evidence of a musical culture in the Middle Paleolithic. Other than the Divje Babe Flute and three other doubtful flutes, there is virtually no surviving Middle Paleolithic musical evidence of any certainty, similar to the situation in regards to visual art. The earliest objects whose designations as musical instruments are widely accepted are bone flutes from the Swabian Jura, Germany, namely from the Geissenklösterle, Hohle Fels and Vogelherd caves. Dated to the Aurignacian (of the Upper Paleolithic) and used by Early European modern humans, from all three caves there are eight examples, four made from the wing bones of birds and four from mammoth ivory; three of these are near complete. Three flutes from the Geissenklösterle are dated as the oldest, c. 43,150–39,370 BP.

Considering the relative complexity of flutes, it is likely earlier instruments existed, akin to objects that are common in later hunter and gatherer societies, such as rattles, shakers and drums. The absence of other instruments from and before this time may be due to their use of weaker—and thus more biodegradable—materials, such as reeds, gourds, skins, and bark. A painting in the Cave of the Trois-Frères dating to c. 15,000 BCE is thought to depict a shaman playing a musical bow.

Prehistoric cultures are thought to have had a wide variety of uses for music, with little unification between different societies. Music was likely in particular value when food and other basic needs were scarce. It is also probable that prehistoric cultures viewed music as intrinsically connected with nature, and may have believed its use influenced the natural world directly.

The earliest instruments found in prehistoric China are 12 gudi bone flutes in the modern-day Jiahu, Wuyang, Henan Province from c. 6000 BCE. The only instruments dated to the prehistoric Xia dynasty (c. 2070–1600) are two qing, two small bells (one earthenware, one bronze) and a xun. Due to this extreme scarcity of surviving instruments and the general uncertainty surrounding most of the Xia, creating a musical narrative of the period is impractical. In the Indian subcontinent, the prehistoric Indus Valley Civilisation (from c. 2500–2000 BCE in its mature state) has archeological evidence that indicates simple rattles and vessel flutes were used, while iconographical evidence suggests early harps and drums also existed. An ideogram in the later IVC contains the earliest known depiction of an arched harp, dated sometime before 1800 BCE.

Ancient music

Drawing of the tablet with the Hymn to Nikkal (c. 1400 BCE), the oldest of the Hurrian songs

Following the advent of writing, literate civilizations are termed part of the ancient world, a periodization which extends from the first Sumerian literature of Abu Salabikh (now Southern Iraq) of c. 2600 BCE, until the Post-classical era of the 6th century CE. Though the music of Ancient societies was extremely diverse, some fundamental concepts arise prominently in virtually all of them, namely monophony, improvisation and the dominance of text in musical settings. Varying song forms were present in Ancient cultures, including China, Egypt, Greece, India, Mesopotamia, Rome and the Middle East. The text, rhythm and melodies of these songs were closely aligned, as was music in general, with magic, science and religion. Complex song forms developed in later ancient societies, particularly the national festivals of China, Greece and India. Later Ancient societies also saw increased trade and transmission of musical ideas and instruments, often shepherded by the Silk Road. For example, a tuning key for a qin-zither from 4th–5th centuries BCE China includes considerable Persian iconography. In general, not enough information exists to make many other generalizations about ancient music.

The few actual examples of ancient music notation that survive usually exist on papyrus or clay tablets. Information on musical practices, genres and thought is mainly available through literature, visual depictions and increasingly as the period progresses, instruments. The oldest surviving written music is the Hurrian songs from Ugarit, Syria. Of these, the oldest is the Hymn to Nikkal (hymn no. 6; h. 6), which is somewhat complete and dated to c. 1400 BCE. However, the Seikilos epitaph is the earliest entirely complete noted musical composition. Dated to the 2nd-Century CE or later, it is an epitaph, perhaps for the wife of the unknown Seikilos.

China

Shang and Zhou

They strike the bells, kin, kin,
They play the se-zither, play the qin-zither,
The mouth organ and chime stones sound together;
They sing the Ya and Nan Odes,
And perform flawlessly upon their flutes.

Shijing, Ode 208, Gu Zhong
Translated by John S. Major

By the mid-13th century BCE, the late Shang dynasty (1600–1046 BCE) had developed writing, which mostly exists as divinatory inscriptions on the ritualistic oracle bones but also as bronze inscriptions. As many as 11 oracle script characters may refer to music to some extent, some of which could be iconographical representations of instruments themselves. The stone bells qing appears to have been particularly popular with the Shang ruling class, and while no surviving flutes have been dated to the Shang, oracle script evidence suggests they used ocarinas (xun), transverse flute (xiao and dizi), douple pipes, the mouthorgan (sheng), and maybe the pan flute (paixiao). Due to the advent of the bronze in 2000 BCE, the Shang used the material for bells—the ling [zh] (鈴), nao [zh] (鐃) and zhong (鐘)—that can be differentiated in two ways: those with or without a clapper and those struck on the inside or outside. Drums, which are not found from before the Shang, sometimes used bronze, though they were more often wooden (bangu). The aforementioned wind instruments certainly existed by the Zhou dynasty (1046–256 BCE), as did the first Chinese string instruments: the guqin (or qin) and se zithers.[66][n 19] The Zhou saw the emergence of major court ensembles and the well known Tomb of Marquis Yi of Zeng (after 433 BCE) contains a variety of complex and decorated instruments. Of the tomb, the by-far most notable instrument is the monumental set of 65 tuned bianzhong bells, which range five octaves requiring at least five players; they are still playable and include rare inscriptions on music.

The monumental Bianzhong of Marquis Yi of Zeng, c. 5th century BCE, from Hubei

Ancient Chinese instruments served both practical and ceremonial means. People used them to appeal to supernatural forces for survival needs, while pan flutes may have been used to attract birds while hunting, and drums were common in sacrifices and military ceremonies. Chinese music has always been closely associated with dance, literature and fine arts; many early Chinese thinkers also equated music with proper morality and governance of society. Throughout the Shang and Zhou music was a symbol of power for the Imperial court, being utilized in religious services as well as the celebration of ancestors and heroes. Confucius (c. 551–479) formally designated the music concerned with ritual and ideal morality as the superior yayue (雅樂; "proper music"), in opposition to suyue (俗樂; "vernacular/popular music"), which included virtually all non-ceremonial music, but particularly any that was considered excessive or lascivious. During the Warring States Period when of Confucius's lifetime, officials often ignored this distinction, preferring more lively suyue music and using the older yayue traditional solely for political means. Confucius and disciples such as Mencius considered this preference virtueless and saw ill of the leaders' ignorance of ganying, a theory that held music was intrinsically connected to the universe. Thus, many aspects of Ancient Chinese music were aligned with cosmology: the 12 pitch shí-èr-lǜ system corresponded equally with certain weights and measurements; the pentatonic scale with the five wuxing; and the eight tone classification of Chinese instruments of bayin with the eight symbols of bagua. No actual music or texts on the performance practices of Ancient Chinese musicians survive. The Five Classics of the Zhou dynasty include musical commentary; the I Ching and Chunqiu Spring and Autumn Annals make references, while the Liji Book of Rites contains a substantial discussion (see the chapter Yue Ji Record of Music). While the Yue Jing Classic of Music is lost, the Shijing Classic of Poetry contains 160 texts to now lost songs from the Western Zhou period (1045–771).

Qin and Han

Two musicians of the Eastern Han Dynasty (25–220 CE), Shanghai Museum

The Qin dynasty (221–206 BCE), established by Qin Shi Huang, lasted for only 15 years, but the purported burning of books resulted in a substantial loss of previous musical literature. The Qin saw the guzheng become a particularly popular instrument; as a more portable and louder zither, it meet the needs of an emerging popular music scene. During the Han dynasty (202 BCE – 220 CE), there were attempts to reconstruct the music of the Shang and Zhou, as it was now "idealized as perfect". A Music Bureau, the Yuefu, was founded or at its height by at least 120 BCE under Emperor Wu of Han, and was responsible for collecting folksongs. The purpose of this was twofold; it allowed the Imperial Court to properly understand the thoughts of the common people, and it was also an opportunity for the Imperial Court to adapt and manipulate the songs to suit propaganda and political purposes. Employing ceremonial, entertainment-oriented and military musicians, the Bureau also performed at a variety of venues, wrote new music, and set music to commissioned poetry by noted figures such as Sima Xiangru. The Han dynasty had officially adopted Confucianism as the state philosophy, and the ganying theories became a dominant philosophy. In practice, however, many officials ignored or downplayed Confucius's high regard for yayue over suyue music, preferring to engage in the more lively and informal later. By 7 BCE the Bureau employed 829 musicians; that year Emperor Ai either disbanded or downsized the department, due to financial limitations, and the Bureau's increasingly prominent suyue music which conflicted with Confucianism. The Han dynasty saw a preponderance of foreign musical influences from the Middle East and Central Asia: the emerging Silk Road led to the exchange of musical instruments, and allowed travelers such as Zhang Qian to relay with new musical genres and techniques. Instruments from said cultural transmission include metal trumpets and instruments similar to the modern oboe and oud lute, the latter which became the pipa. Other preexisting instruments greatly increased in popularity, such as the qing, panpipes, and particularly the qin, which was from then on the most revered instrument, associated with good character and morality.

Greece

Greek written history extends far back into Ancient Greece, and was a major part of ancient Greek theatre. In ancient Greece, mixed-gender choruses performed for entertainment, celebration and spiritual reasons. Instruments included the most important wind instrument, the double-reed aulos, as well as the plucked string instrument, the lyre, especially the special kind called a kithara.

India

The principal sources on the music of ancient India are textual and iconographical; specifically, some theoretical treatises in Sanskrit survive, there are brief mentions in general literature and many sculptures of Ancient Indian musicians and their instruments exist. Ancient Sanskrit, Pali, and Prakrit literature frequently contains musical references, from the Vedas to the works of Kalidasa and the Ilango Adigal's epic Silappatikaram.[122] Despite this, little is known on the actual musical practices of ancient India and the information available forces a somewhat homogeneous perspective on the music of the time, even though evidence indicates that in reality it was far more diverse.

The monumental arts treatise Natya Shastra is among the earliest and chief sources for Ancient Indian music; the music portions alone are likely from the Gupta period (4th century to 6th century CE). The religious text Rigveda has elements of present Indian music, with a musical notation to denote the metre and the mode of chanting.

Persia and Mesopotamia

Up to the Achaemenid period

The Bull Headed Lyre of Ur, found in the Royal Cemetery at Ur, is the best known of the ancient Lyres of Ur

In general, it is impossible to create a thorough outline of the earliest music in Persia due to a paucity of surviving records. Evidenced by c. 3300–3100 BCE Elam depictions, arched harps are the first affirmation Persian music, though it is probable that they existed well before their artistic depictions. Elamite bull lyres from c. 2450 have been found in Susa, while more than 40 small Oxus trumpets have been found in Bactria and Margiana, dated to the c. 2200–1750 Bactria–Margiana Archaeological Complex. The oxus trumpets seem to have had a close association with both religion and animals; a Zoroastrian myth in which Jamshid attract animals with the trumpet suggests that the Elamites used them for hunting. In many ways the earliest known musical cultures of Iran are strongly connected with those of Mesopotamia. Ancient arched harps (c. 3000) also exist in the latter and the scarcity of instruments make it unclear as to which culture the harp originated. Far more bull lyres survive in Ur of Mesopotamia, notably the Bull Headed Lyre of Ur, though they are nearly identical to their contemporary Elamite counterparts. From evidence in terracotta plaques, by the 2nd-century BCE the arched harp was displaced by the angular harps, which existed in 20-string vertical and nine-string horizontal variants. Lutes were purportedly used in Mesopotamia by at least 2300 BCE, but not until c. 1300 BCE do the appear in Iran, where they became the dominant string instruments of Western Iran, though the available evidence suggests its popularity was outside of the elite. The rock reliefs of Kul-e Farah show that sophisticated Persian court ensembles emerged in the 1st-century BCE, in the which the central instrument was the arched harp. The prominence of musicians in these certain rock reliefs suggests they were essential in religious ceremonies.

Like earlier periods, extremely little contemporary information on the music of the Achaemenid Empire (550–330 BCE) exists. Most knowledge on the Achaemenid musical culture comes from Greek historians. In his Histories, Herodotus noted that Achamenid priests did not use aulos music in their ceremonies, while Xenophon reflected on his visit to Persia in the Cyropaedia, mentioning the presence of many female singers at court. Athenaeus also mentions female singers when noting that 329 of them had been taken from the King of Kings Darius III by Macedonian general Parmenion. Later Persian texts assert that gōsān poet-musician minstrels were prominent and of considerable status in court.

Parthian and Sasanian periods

c. 379 CE Bas relief of Sassanid women playing the chang in Taq-e Bostan, Iran

The Parthian Empire (247 BCE to 224 CE) saw an increase in textual and iconographical depictions of musical activity and instruments. 2nd century BCE Parthian rhuta (drinking horns) found in the ancient capital of Nisa include some of the most vivid depictions of musicians from the time. Pictorial evidence such as terracotta plaques show female harpists, while plaques from Babylon show panpipess, as well as string (harps, lutes and lyres) and percussion instruments (tambourines and clappers). Bronze statues from Dura-Europos depict larger panpipes and a double aulos. Music was evidently used in ceremonies and celebrations; a Parthian-era stone frieze in Hatra shows a wedding where musicians are included, playing trumpets, tambourines and a variety of flutes. Other textual and iconographical evidence indicates the continued prominence of gōsān minstrels. However, like the Achaemenid period, Greek writers continue to be a major source for information on Parthian music. Strabo recorded that the gōsān learned songs telling tales of gods and noble men, while Plutarch similarly records the gōsān lauding Parthian heroes and mocking Roman ones. Plutarch also records, much to his bafflement, that rhoptra (large drums) were used by the Parthian army to prepare for war.

The Sasanian period (226–651 CE), however, has left ample evidence of music. This influx of Sasanian records suggests a prominent musical culture in the Empire, especially in the areas dominated by Zoroastrianism. Many Sassanian Shahanshahs were ardent supporters of music, including the founder of the empire Ardashir I and Bahram V. Khosrow II (r. 590–628) was the most outstanding patron, his reign being regarded as a golden age of Persian music. Musicians in Khosrow's service include Āzādvar-e Changi,[n 26] Bamshad, the harpist Nagisa (Nakisa), Ramtin, Sarkash and Barbad, who was the most famous. These musicians were usually active as minstrels, which were performers who worked as both court poets and musicians; in the Sassanian Empire there was little distinction between poetry and music.

Other Arab and African cultures

The Western African Nok culture (modern-day Nigeria) existed from c. 500–200 BCE and left a considerable amount of sculptures. Among these are depictions of music, such as a man who shakes two objects thought to be maracas. Another sculpture includes a man with his mouth opening (possibly singing) while there is also a sculpture of a man playing a drum.

Post-classical music

Medieval

Alleluia nativitas by Perotin from the Codex Guelf.1099

Modern scholars generally define 'Medieval music' as the music of Western Europe during the Middle Ages, from approximately the 6th to 15th centuries. Music was certainly prominent in the Early Middle Ages, as attested by artistic depictions of instruments, writings about music, and other records; however, the only repertory of music which has survived from before 800 to the present day is the plainsong liturgical music of the Roman Catholic Church, the largest part of which is called Gregorian chant. Pope Gregory I, who gave his name to the musical repertory and may himself have been a composer, is usually claimed to be the originator of the musical portion of the liturgy in its present form, though the sources giving details on his contribution date from more than a hundred years after his death. Many scholars believe that his reputation has been exaggerated by legend. Most of the chant repertory was composed anonymously in the centuries between the time of Gregory and Charlemagne.

During the 9th century several important developments took place. First, there was a major effort by the Church to unify the many chant traditions, and suppress many of them in favor of the Gregorian liturgy. Second, the earliest polyphonic music was sung, a form of parallel singing known as organum. Third, and of greatest significance for music history, notation was reinvented after a lapse of about five hundred years, though it would be several more centuries before a system of pitch and rhythm notation evolved having the precision and flexibility that modern musicians take for granted.

Several schools of polyphony flourished in the period after 1100: the St. Martial school of organum, the music of which was often characterized by a swiftly moving part over a single sustained line; the Notre Dame school of polyphony, which included the composers Léonin and Pérotin, and which produced the first music for more than two parts around 1200; the musical melting-pot of Santiago de Compostela in Galicia, a pilgrimage destination and site where musicians from many traditions came together in the late Middle Ages, the music of whom survives in the Codex Calixtinus; and the English school, the music of which survives in the Worcester Fragments and the Old Hall Manuscript. Alongside these schools of sacred music a vibrant tradition of secular song developed, as exemplified in the music of the troubadours, trouvères and Minnesänger. Much of the later secular music of the early Renaissance evolved from the forms, ideas, and the musical aesthetic of the troubadours, courtly poets and itinerant musicians, whose culture was largely exterminated during the Albigensian Crusade in the early 13th century.

Forms of sacred music which developed during the late 13th century included the motet, conductus, discant, and clausulae. One unusual development was the Geisslerlieder, the music of wandering bands of flagellants during two periods: the middle of the 13th century (until they were suppressed by the Church); and the period during and immediately following the Black Death, around 1350, when their activities were vividly recorded and well-documented with notated music. Their music mixed folk song styles with penitential or apocalyptic texts. The 14th century in European music history is dominated by the style of the ars nova, which by convention is grouped with the medieval era in music, even though it had much in common with early Renaissance ideals and aesthetics. Much of the surviving music of the time is secular, and tends to use the formes fixes: the ballade, the virelai, the lai, the rondeau, which correspond to poetic forms of the same names. Most pieces in these forms are for one to three voices, likely with instrumental accompaniment: famous composers include Guillaume de Machaut and Francesco Landini.

Byzantine

Prominent and diverse musical practices were present in the Byzantine Empire, which existed by 395 to 1453. Both sacred and secular music were commonplace, with sacred music frequently used in church services and secular music in many events including, ceremonies dramas, ballets, banquets, festivals and sports games. However, despite its popularity, secular Byzantine music was harshly criticized by the Church Fathers. Composers of sacred music, especially hymns and chants, are generally well documented throughout the history of Byzantine music. However, those before the reign of Justinian I are virtually unknown; the monks Anthimos, Auxentios and Timokles are said to have written troparia, but only the text to a single one by Auxentios survives. The first major form was the kontakion, of which Romanos the Melodist was the foremost composer. In the late 7th century the kanōn overtook the kontakion in popularity; Andrew of Crete became its first significant composer, and is traditionally credited as the genre's originator, though modern scholars now doubt this attribution. The kañon reached its peak with the music of John of Damascus and Cosmas of Maiuma and later Theodore of Stoudios and Theophanes the Branded in the 8th and 9th centuries respectively. Composers of secular music are considerably less documented. Not until late in the empire's history are composers known by name, with Joannes Koukouzeles, Xenos Korones and Joannes Glykys as the leading figures.

Like their Western counterparts of the same period, Byzantine composers were primarily men. Kassia is a major exception to this; she was a prolific and important composer of sticheron hymns and the only woman whose works entered the Byzantine liturgy. A few other women are known to have been composers, Thekla, Theodosia, Martha and the daughter of John Kladas (her given name is unrecorded). Only the latter has any surviving work, a single antiphon. Some Byzantine emperors are known to have been composers, such as Leo VI the Wise and Constantine VII.

Early modern and modern music

Indian classical music

During the ancient and medieval periods, the classical music of the Indian subcontinent was a largely unified practice. By the 14th century, socio-political turmoil inaugurated by the Delhi Sultanate began to isolate Northern and Southern India, and independent traditions in each region began emerging. By the 16th-century two distinct styles had formed: the Hindustani classical music of the North and the Carnatic classical music of the South. One of the major differences between them is that the Northern Hindustani vein was considerably influenced by the Persian and Arab musical practices of the time. Carnatic music is largely devotional; the majority of the songs are addressed to the Hindu deities.

Indian classical music (marga) is monophonic and based on a single melody line or raga rhythmically organized through talas.

Western classical music

Renaissance

Guillaume Du Fay (left), with Gilles Binchois (right) in a c. 1440 Illuminated manuscript copy of Martin le Franc's Le champion des dames

The beginning of the Renaissance in music is not as clearly marked as the beginning of the Renaissance in the other arts, and unlike in the other arts, it did not begin in Italy, but in northern Europe, specifically in the area currently comprising central and northern France, the Netherlands, and Belgium. The style of the Burgundian composers, as the first generation of the Franco-Flemish school is known, was at first a reaction against the excessive complexity and mannered style of the late 14th century ars subtilior, and contained clear, singable melody and balanced polyphony in all voices. The most famous composers of the Burgundian school in the mid-15th century are Guillaume Dufay, Gilles Binchois, and Antoine Busnois.

By the middle of the 15th century, composers and singers from the Low Countries and adjacent areas began to spread across Europe, especially into Italy, where they were employed by the papal chapel and the aristocratic patrons of the arts (such as the Medici, the Este, and the Sforza families). They carried their style with them: smooth polyphony which could be adapted for sacred or secular use as appropriate. Principal forms of sacred musical composition at the time were the mass, the motet, and the laude; secular forms included the chanson, the frottola, and later the madrigal.

The invention of printing had an immense influence on the dissemination of musical styles, and along with the movement of the Franco-Flemish musicians, contributed to the establishment of the first truly international style in European music since the unification of Gregorian chant under Charlemagne. Composers of the middle generation of the Franco-Flemish school included Johannes Ockeghem, who wrote music in a contrapuntally complex style, with varied texture and an elaborate use of canonical devices; Jacob Obrecht, one of the most famous composers of masses in the last decades of the 15th century; and Josquin des Prez, probably the most famous composer in Europe before Palestrina, and who during the 16th century was renowned as one of the greatest artists in any form. Music in the generation after Josquin explored increasing complexity of counterpoint; possibly the most extreme expression is in the music of Nicolas Gombert, whose contrapuntal complexities influenced early instrumental music, such as the canzona and the ricercar, ultimately culminating in Baroque fugal forms.

By the middle of the 16th century, the international style began to break down, and several highly diverse stylistic trends became evident: a trend towards simplicity in sacred music, as directed by the Counter-Reformation Council of Trent, exemplified in the music of Giovanni Pierluigi da Palestrina; a trend towards complexity and chromaticism in the madrigal, which reached its extreme expression in the avant-garde style of the Ferrara School of Luzzaschi and the late century madrigalist Carlo Gesualdo; and the grandiose, sonorous music of the Venetian school, which used the architecture of the Basilica San Marco di Venezia to create antiphonal contrasts. The music of the Venetian school included the development of orchestration, ornamented instrumental parts, and continuo bass parts, all of which occurred within a span of several decades around 1600. Famous composers in Venice included the Gabrielis, Andrea and Giovanni, as well as Claudio Monteverdi, one of the most significant innovators at the end of the era.

Most parts of Europe had active and well-differentiated musical traditions by late in the century. In England, composers such as Thomas Tallis and William Byrd wrote sacred music in a style similar to that written on the continent, while an active group of home-grown madrigalists adapted the Italian form for English tastes: famous composers included Thomas Morley, John Wilbye and Thomas Weelkes. Spain developed instrumental and vocal styles of its own, with Tomás Luis de Victoria writing refined music similar to that of Palestrina, and numerous other composers writing for the new guitar. Germany cultivated polyphonic forms built on the Protestant chorales, which replaced the Roman Catholic Gregorian Chant as a basis for sacred music, and imported the style of the Venetian school (the appearance of which defined the start of the Baroque era there). In addition, German composers wrote enormous amounts of organ music, establishing the basis for the later Baroque organ style which culminated in the work of J.S. Bach. France developed a unique style of musical diction known as musique mesurée, used in secular chansons, with composers such as Guillaume Costeley and Claude Le Jeune prominent in the movement.

One of the most revolutionary movements in the era took place in Florence in the 1570s and 1580s, with the work of the Florentine Camerata, who ironically had a reactionary intent: dissatisfied with what they saw as contemporary musical depravities, their goal was to restore the music of the ancient Greeks. Chief among them were Vincenzo Galilei, the father of the astronomer, and Giulio Caccini. The fruits of their labors was a declamatory melodic singing style known as monody, and a corresponding staged dramatic form: a form known today as opera. The first operas, written around 1600, also define the end of the Renaissance and the beginning of the Baroque eras.

Music prior to 1600 was modal rather than tonal. Several theoretical developments late in the 16th century, such as the writings on scales on modes by Gioseffo Zarlino and Franchinus Gaffurius, led directly to the development of common practice tonality. The major and minor scales began to predominate over the old church modes, a feature which was at first most obvious at cadential points in compositions, but gradually became pervasive. Music after 1600, beginning with the tonal music of the Baroque era, is often referred to as belonging to the common practice period.

Baroque

The Baroque era took place from 1600 to 1750, as the Baroque artistic style flourished across Europe and, during this time, music expanded in its range and complexity. Baroque music began when the first operas (dramatic solo vocal music accompanied by orchestra) were written. During the Baroque era, polyphonic contrapuntal music, in which multiple, simultaneous independent melody lines were used, remained important (counterpoint was important in the vocal music of the Medieval era). German, Italian, French, Dutch, Polish, Spanish, Portuguese, and English Baroque composers wrote for small ensembles including strings, brass, and woodwinds, as well as for choirs and keyboard instruments such as pipe organ, harpsichord, and clavichord. During this period several major music forms were defined that lasted into later periods when they were expanded and evolved further, including the fugue, the invention, the sonata, and the concerto. The late Baroque style was polyphonically complex and richly ornamented. Important composers from the Baroque era include Johann Sebastian Bach, Arcangelo Corelli, François Couperin, Girolamo Frescobaldi, George Frideric Handel, Jean-Baptiste Lully, Claudio Monteverdi, Georg Philipp Telemann and Antonio Vivaldi.

Classical

The principal composers of the Classical period and the transition to Romanticism, collectively known as the First Viennese School. Clockwise, from top left: Joseph Haydn (Hardy, 1791); Wolfgang Amadeus Mozart (della Croce, 1781); Ludwig van Beethoven (Stieler, 1820); and Franz Schubert (Rieder, 1875).

The music of the Classical period is characterized by homophonic texture, or an obvious melody with accompaniment. These new melodies tended to be almost voice-like and singable, allowing composers to actually replace singers as the focus of the music. Instrumental music therefore quickly replaced opera and other sung forms (such as oratorio) as the favorite of the musical audience and the epitome of great composition. However, opera did not disappear: during the classical period, several composers began producing operas for the general public in their native languages (previous operas were generally in Italian).

Along with the gradual displacement of the voice in favor of stronger, clearer melodies, counterpoint also typically became a decorative flourish, often used near the end of a work or for a single movement. In its stead, simple patterns, such as arpeggios and, in piano music, Alberti bass (an accompaniment with a repeated pattern typically in the left hand), were used to liven the movement of the piece without creating a confusing additional voice. The now-popular instrumental music was dominated by several well-defined forms: the sonata, the symphony, and the concerto, though none of these were specifically defined or taught at the time as they are now in music theory. All three derive from sonata form, which is both the overlying form of an entire work and the structure of a single movement. Sonata form matured during the Classical era to become the primary form of instrumental compositions throughout the 19th century.

The early Classical period was ushered in by the Mannheim School, which included such composers as Johann Stamitz, Franz Xaver Richter, Carl Stamitz, and Christian Cannabich. It exerted a profound influence on Joseph Haydn and, through him, on all subsequent European music. Wolfgang Amadeus Mozart was the central figure of the Classical period, and his phenomenal and varied output in all genres defines our perception of the period. Ludwig van Beethoven and Franz Schubert were transitional composers, leading into the Romantic period, with their expansion of existing genres, forms, and even functions of music.

Romantic

In the Romantic period, music became more expressive and emotional, expanding to encompass literature, art, and philosophy. Famous early Romantic composers include Schumann, Chopin, Mendelssohn, Bellini, Donizetti, and Berlioz. The late 19th century saw a dramatic expansion in the size of the orchestra, and in the role of concerts as part of urban society. Famous composers from the second half of the century include Johann Strauss II, Brahms, Liszt, Tchaikovsky, Verdi, and Wagner. Between 1890 and 1910, a third wave of composers including Grieg, Dvořák, Mahler, Richard Strauss, Puccini, and Sibelius built on the work of middle Romantic composers to create even more complex – and often much longer – musical works. A prominent mark of late 19th century music is its nationalistic fervor, as exemplified by such figures as Dvořák, Sibelius, and Grieg. Other prominent late-century figures include Saint-Saëns, Fauré, Rachmaninoff, Franck, Debussy and Rimsky-Korsakov.

20th and 21st-century music

Music of all kinds also became increasingly portable. The 20th century saw a revolution in music listening as the radio gained popularity worldwide and new media and technologies were developed to record, capture, reproduce and distribute music. Music performances became increasingly visual with the broadcast and recording of performances.

20th-century music brought a new freedom and wide experimentation with new musical styles and forms that challenged the accepted rules of music of earlier periods. The invention of musical amplification and electronic instruments, especially the synthesizer, in the mid-20th century revolutionized classical and popular music, and accelerated the development of new forms of music.

As for classical music, two fundamental schools determined the course of the century: that of Arnold Schoenberg and that of Igor Stravinsky. However, other composers also had a notable influence. For example: Béla Bartók, Anton Webern, Dmitri Shostakovich, Olivier Messiaen, John Cage, Benjamin Britten, Karlheinz Stockhausen, Sofya Gubaidulina, Krzysztof Penderecki, Brian Ferneyhough, Kaija Saariaho.

The 20th century saw the unprecedented dissemination of popular music, that is, music with a wide appeal. The term has its roots in the music of the American Tin Pan Alley, a group of prominent the began during the 1880s in New York City. Although popular music sometimes is known as "pop music", the two terms are not interchangeable. Popular music is a generic term for a wide variety of genres of music that appeal to the tastes of a large segment of the population, whereas pop music usually refers to a specific musical genre within popular music. Popular music songs and pieces typically have easily singable melodies. The song structure of popular music commonly involves repetition of sections, with the verse and chorus or refrain repeating throughout the song and the bridge providing a contrasting and transitional section within a piece.

Music history

From Wikipedia, the free encyclopedia
 
A famous Tang Dynasty guqin "Jiu Huan Pei". The guqin has been played since ancient times, and has traditionally been favored by scholars and literati as an instrument of great subtlety and refinement.

Music history, sometimes called historical musicology, is a highly diverse subfield of the broader discipline of musicology that studies music from a historical point of view. In theory, "music history" could refer to the study of the history of any type or genre of music (e.g., the history of Indian music or the history of rock). In practice, these research topics are often categorized as part of ethnomusicology or cultural studies, whether or not they are ethnographically based. The terms "music history" and "historical musicology" usually refer to the history of the notated music of Western elites, sometimes called "art music" (by analogy to art history, which tends to focus on elite art).

The methods of music history include source studies (esp. manuscript studies), paleography, philology (especially textual criticism), style criticism, historiography (the choice of historical method), musical analysis, and iconography. The application of musical analysis to further these goals is often a part of music history, though pure analysis or the development of new tools of music analysis is more likely to be seen in the field of music theory. Some of the intellectual products of music historians include peer-reviewed articles in journals, university press-published music history books, university textbooks, new editions of musical works, biographies of composers and other musicians, studies of the relationship between words and music, and reflections upon the role of music in society.

Pedagogy

Although most performers of classical and traditional instruments receive some instruction in music history, whether this is the history or art music, pop, or rock and roll, etc. These from their music teachers throughout their lessons and high school classes, the majority of formal music history courses are offered at the post-secondary (college or university) level. In Canada, some music students receive training prior to undergraduate studies because examinations in music history (as well as music theory) are required to complete Royal Conservatory of Music certification at the Grade 9 level and higher.

Most medium and large institutions will offer music appreciation courses for non-music majors and music history courses for music majors. The two types of courses will usually differ in length (one to two semesters vs. two to four), breadth (many music appreciation courses begin at the late Baroque or classical eras and might omit music after WWII while courses for music majors traditionally span the period from the Middle Ages to the current era), and depth. Both types of courses tend to emphasize a balance among the acquisition of musical repertory (often emphasized through listening examinations), study and analysis of these works, biographical and cultural details of music and musicians, and writing about music, perhaps through music criticism. Most music history courses in university examine the following eras: Medieval (c. 1150 - c. 1400), Renaissance (c. 1400 - c. 1600), Baroque (c. 1600 - c. 1750), Classical (c. 1750 - c. 1830), Early Romantic (c. 1830 - c. 1860) Late Romantic (c. 1860 - c. 1920) Post 'Great War' Years (c. 1920 - Present).

More specialized seminars in music history tend to use a similar approach on a narrower subject while introducing more of the tools of research in music history. The range of possible topics is virtually limitless. Some examples might be "Music during World War I," "Medieval and Renaissance instrumental music," "Music and politics," "Mozart's Don Giovanni, or Women and music."

The methods and tools of music history are nearly as many as its subjects and therefore make a strict categorization impossible. However, a few trends and approaches can be outlined here. Like in any other historical discipline, most research in music history can be roughly divided into two categories: the establishing of factual and correct data and the interpretation of data. Most historical research does not fall into one category solely, but rather employs a combination of methods from both categories. The act of establishing factual data can never be fully separate from the act of interpretation.

Archival work may be conducted to find connections to music or musicians in a collection of documents of broader interests (e.g., Vatican pay records, letters to a patroness of the arts) or to more systematically study a collection of documents related to a musician. In some cases, where records, scores, and letters have been digitized, archival work can be done online. One example of a composer for whom archival materials can be examined online is the Arnold Schoenberg Center.

Performance practice draws on many of the tools of historical musicology to answer the specific question of how music was performed in various places at various times in the past. Scholars investigate questions such as which instruments or voices were used to perform a given work, what tempos (or tempo changes) were used, and how (or if) ornaments were used. Although performance practice was previously confined to early music from the Baroque era, since the 1990s, research in performance practice has examined other historical eras, such as how early Classical era piano concerti were performed, how the early history of recording affected the use of vibrato in classical music, or which instruments were used in Klezmer music.

Biographical studies of composers can give us a better sense of the chronology of compositions, influences on style and works, and provide important background to the interpretation (by performers or listeners) of works. Thus biography can form one part of the larger study of the cultural significance, underlying program, or agenda of a work; a study which gained increasing importance in the 1980s and early 1990s.

Sociological studies focus on the function of music in society as well as its meaning for individuals and society as a whole. Researchers emphasizing the social importance of music (including classical music) are sometimes called New musicologists. They may examine the intersection of music and music-making with issues such as race, class, gender, sexuality (e.g. LGBTQ), and disability, among other approaches.

Semiotic studies are most conventionally the province of music analysts rather than historians. However, crucial to the practice of musical semiotics – the interpretation of meaning in a work or style – is its situation in a historical context. The interpretative work of scholars such as Kofi Agawu and Lawrence Kramer fall between the analytic and the music historical.

History

Before 1800

The first studies of Western musical history date back to the middle of the 18th century. G.B. Martini published a three volume history titled Storia della musica (History of Music) between 1757 and 1781. Martin Gerbert published a two volume history of sacred music titled De cantu de musica sacra in 1774. Gerbert followed this work with a three volume work Scriptores ecclesiastici de musica sacra containing significant writings on sacred music from the 3rd century onwards in 1784.

1800–1950

Ludwig van Beethoven's manuscript sketch for Piano Sonata No. 28, Movement IV, Geschwind, doch nicht zu sehr und mit Entschlossenheit (Allegro), in his own handwriting. The piece was completed in 1816.

In the 20th century, the work of Johannes Wolf and others developed studies in Medieval music and early Renaissance music. Wolf's writings on the history of musical notation are considered to be particularly notable by musicologists. Historical musicology has played a critical role in renewed interest in Baroque music as well as medieval and Renaissance music. In particular, the authentic performance movement owes much to historical musicological scholarship. Towards the middle of the 20th century, musicology (and its largest subfield of historical musicology) expanded significantly as a field of study. Concurrently the number of musicological and music journals increased to create further outlets for the publication of research. The domination of German language scholarship ebbed as significant journals sprang up throughout the West, especially America.

Critiques

Exclusion of disciplines and musics

In its most narrow definition, historical musicology is the music history of Western culture. Such a definition arbitrarily excludes disciplines other than history, cultures other than Western, and forms of music other than "classical" ("art", "serious", "high culture") or notated ("artificial") – implying that the omitted disciplines, cultures, and musical styles/genres are somehow inferior. A somewhat broader definition incorporating all musical humanities is still problematic, because it arbitrarily excludes the relevant (natural) sciences (acoustics, psychology, physiology, neurosciences, information and computer sciences, empirical sociology and aesthetics) as well as musical practice. The musicological sub-disciplines of music theory and music analysis have likewise historically been rather uneasily separated from the most narrow definition of historical musicology.

Within historical musicology, scholars have been reluctant to adopt postmodern and critical approaches that are common elsewhere in the humanities. According to Susan McClary (2000, p. 1285) the discipline of "music lags behind the other arts; it picks up ideas from other media just when they have become outmoded." Only in the 1990s did historical musicologists, preceded by feminist musicologists in the late 1980s, begin to address issues such as gender, sexualities, bodies, emotions, and subjectivities which dominated the humanities for twenty years before (ibid, p. 10). In McClary's words (1991, p. 5), "It almost seems that musicology managed miraculously to pass directly from pre- to postfeminism without ever having to change – or even examine – its ways." Furthermore, in their discussion on musicology and rock music, Susan McClary and Robert Walser also address a key struggle within the discipline: how musicology has often "dismisse[d] questions of socio-musical interaction out of hand, that part of classical music's greatness is ascribed to its autonomy from society." (1988, p. 283)

Exclusion of popular music

According to Richard Middleton, the strongest criticism of (historical) musicology has been that it generally ignores popular music. Though musicological study of popular music has vastly increased in quantity recently, Middleton's assertion in 1990—that most major "works of musicology, theoretical or historical, act as though popular music did not exist"—holds true. Academic and conservatory training typically only peripherally addresses this broad spectrum of musics, and many (historical) musicologists who are "both contemptuous and condescending are looking for types of production, musical form, and listening which they associate with a different kind of music...'classical music'...and they generally find popular music lacking"

He cites three main aspects of this problem (p. 104–6). The terminology of historical musicology is "slanted by the needs and history of a particular music ('classical music')." He acknowledges that "there is a rich vocabulary for certain areas [harmony, tonality, certain part-writing and forms], important in musicology's typical corpus"; yet he points out that there is "an impoverished vocabulary for other areas [rhythm, pitch nuance and gradation, and timbre], which are less well developed" in Classical music. Middleton argues that a number of "terms are ideologically loaded" in that "they always involve selective, and often unconsciously formulated, conceptions of what music is."

As well, he claims that historical musicology uses "a methodology slanted by the characteristics of notation," 'notational centricity' (Tagg 1979, p. 28–32). As a result, "musicological methods tend to foreground those musical parameters which can be easily notated" such as pitch relationships or the relationship between words and music. On the other hand, historical musicology tends to "neglect or have difficulty with parameters which are not easily notated", such as tone colour or non-Western rhythms. In addition, he claims that the "notation-centric training" of Western music schools "induces particular forms of listening, and these then tend to be applied to all sorts of music, appropriately or not". As a result, Western music students trained in historical musicology may listen to a funk or Latin song that is very rhythmically complex, but then dismiss it as a low-level musical work because it has a very simple melody and only uses two or five chords.

Notational centricity also encourages "reification: the score comes to be seen as 'the music', or perhaps the music in an ideal form." As such, music that does not use a written score, such as jazz, blues, or folk, can become demoted to a lower level of status. As well, historical musicology has "an ideology slanted by the origins and development of a particular body of music and its aesthetic...It arose at a specific moment, in a specific context – nineteenth-century Europe, especially Germany – and in close association with that movement in the musical practice of the period which was codifying the very repertory then taken by musicology as the centre of its attention." These terminological, methodological, and ideological problems affect even works sympathetic to popular music. However, it is not "that musicology cannot understand popular music, or that students of popular music should abandon musicology." (Middleton, p. 104).

 

Connectionism

From Wikipedia, the free encyclopedia

Connectionism is an approach in the field of cognitive science that hopes to explain mental phenomena using artificial neural networks (ANN). Connectionism presents a cognitive theory based on simultaneously occurring, distributed signal activity via connections that can be represented numerically, where learning occurs by modifying connection strengths based on experience.

Some advantages of the connectionist approach include its applicability to a broad array of functions, structural approximation to biological neurons, low requirements for innate structure, and capacity for graceful degradation. Some disadvantages include the difficulty in deciphering how ANNs process information, or account for the compositionality of mental representations, and a resultant difficulty explaining phenomena at a higher level.

The success of deep learning networks in the past decade has greatly increased the popularity of this approach, but the complexity and scale of such networks has brought with them increased interpretability problems. Connectionism is seen by many to offer an alternative to classical theories of mind based on symbolic computation, but the extent to which the two approaches are compatible has been the subject of much debate since their inception.

Connectionist (ANN) model with a hidden layer

Basic principles

The central connectionist principle is that mental phenomena can be described by interconnected networks of simple and often uniform units. The form of the connections and the units can vary from model to model. For example, units in the network could represent neurons and the connections could represent synapses, as in the human brain.

Spreading activation

In most connectionist models, networks change over time. A closely related and very common aspect of connectionist models is activation. At any time, a unit in the network has an activation, which is a numerical value intended to represent some aspect of the unit. For example, if the units in the model are neurons, the activation could represent the probability that the neuron would generate an action potential spike. Activation typically spreads to all the other units connected to it. Spreading activation is always a feature of neural network models, and it is very common in connectionist models used by cognitive psychologists.

Neural networks

Neural networks are by far the most commonly used connectionist model today. Though there are a large variety of neural network models, they almost always follow two basic principles regarding the mind:

  1. Any mental state can be described as an (N)-dimensional vector of numeric activation values over neural units in a network.
  2. Memory is created by modifying the strength of the connections between neural units. The connection strengths, or "weights", are generally represented as an N×N matrix.

Most of the variety among neural network models comes from:

  • Interpretation of units: Units can be interpreted as neurons or groups of neurons.
  • Definition of activation: Activation can be defined in a variety of ways. For example, in a Boltzmann machine, the activation is interpreted as the probability of generating an action potential spike, and is determined via a logistic function on the sum of the inputs to a unit.
  • Learning algorithm: Different networks modify their connections differently. In general, any mathematically defined change in connection weights over time is referred to as the "learning algorithm".

Connectionists are in agreement that recurrent neural networks (directed networks wherein connections of the network can form a directed cycle) are a better model of the brain than feedforward neural networks (directed networks with no cycles, called DAG). Many recurrent connectionist models also incorporate dynamical systems theory. Many researchers, such as the connectionist Paul Smolensky, have argued that connectionist models will evolve toward fully continuous, high-dimensional, non-linear, dynamic systems approaches.

Biological realism

Connectionist work in general does not need to be biologically realistic and therefore suffers from a lack of neuroscientific plausibility. However, the structure of neural networks is derived from that of biological neurons, and this parallel in low-level structure is often argued to be an advantage of connectionism in modeling cognitive structures compared with other approaches. One area where connectionist models are thought to be biologically implausible is with respect to error-propagation networks that are needed to support learning, but error propagation can explain some of the biologically-generated electrical activity seen at the scalp in event-related potentials such as the N400 and P600, and this provides some biological support for one of the key assumptions of connectionist learning procedures.

Learning

The weights in a neural network are adjusted according to some learning rule or algorithm, such as Hebbian learning. Thus, connectionists have created many sophisticated learning procedures for neural networks. Learning always involves modifying the connection weights. In general, these involve mathematical formulas to determine the change in weights when given sets of data consisting of activation vectors for some subset of the neural units. Several studies have been focused on designing teaching-learning methods based on connectionism.

By formalizing learning in such a way, connectionists have many tools. A very common strategy in connectionist learning methods is to incorporate gradient descent over an error surface in a space defined by the weight matrix. All gradient descent learning in connectionist models involves changing each weight by the partial derivative of the error surface with respect to the weight. Backpropagation (BP), first made popular in the 1980s, is probably the most commonly known connectionist gradient descent algorithm today.

Connectionism can be traced to ideas more than a century old, which were little more than speculation until the mid-to-late 20th century.

Parallel distributed processing

The prevailing connectionist approach today was originally known as parallel distributed processing (PDP). It was an artificial neural network approach that stressed the parallel nature of neural processing, and the distributed nature of neural representations. It provided a general mathematical framework for researchers to operate in. The framework involved eight major aspects:

  • A set of processing units, represented by a set of integers.
  • An activation for each unit, represented by a vector of time-dependent functions.
  • An output function for each unit, represented by a vector of functions on the activations.
  • A pattern of connectivity among units, represented by a matrix of real numbers indicating connection strength.
  • A propagation rule spreading the activations via the connections, represented by a function on the output of the units.
  • An activation rule for combining inputs to a unit to determine its new activation, represented by a function on the current activation and propagation.
  • A learning rule for modifying connections based on experience, represented by a change in the weights based on any number of variables.
  • An environment that provides the system with experience, represented by sets of activation vectors for some subset of the units.

A lot of the research that led to the development of PDP was done in the 1970s, but PDP became popular in the 1980s with the release of the books Parallel Distributed Processing: Explorations in the Microstructure of Cognition - Volume 1 (foundations) and Volume 2 (Psychological and Biological Models), by James L. McClelland, David E. Rumelhart and the PDP Research Group. The books are now considered seminal connectionist works, and it is now common to fully equate PDP and connectionism, although the term "connectionism" is not used in the books. Following the PDP model, researchers have theorized systems based on the principles of perpendicular distributed processing (PDP).

Earlier work

PDP's direct roots were the perceptron theories of researchers such as Frank Rosenblatt from the 1950s and 1960s. But perceptron models were made very unpopular by the book Perceptrons by Marvin Minsky and Seymour Papert, published in 1969. It demonstrated the limits on the sorts of functions that single-layered (no hidden layer) perceptrons can calculate, showing that even simple functions like the exclusive disjunction (XOR) could not be handled properly. The PDP books overcame this limitation by showing that multi-level, non-linear neural networks were far more robust and could be used for a vast array of functions.

Many earlier researchers advocated connectionist style models, for example in the 1940s and 1950s, Warren McCulloch and Walter Pitts (MP neuron), Donald Olding Hebb, and Karl Lashley. McCulloch and Pitts showed how neural systems could implement first-order logic: Their classic paper "A Logical Calculus of Ideas Immanent in Nervous Activity" (1943) is important in this development here. They were influenced by the important work of Nicolas Rashevsky in the 1930s. Hebb contributed greatly to speculations about neural functioning, and proposed a learning principle, Hebbian learning, that is still used today. Lashley argued for distributed representations as a result of his failure to find anything like a localized engram in years of lesion experiments.

Connectionism apart from PDP

Though PDP is the dominant form of connectionism, other theoretical work should also be classified as connectionist.

Many connectionist principles can be traced to early work in psychology, such as that of William James. Psychological theories based on knowledge about the human brain were fashionable in the late 19th century. As early as 1869, the neurologist John Hughlings Jackson argued for multi-level, distributed systems. Following from this lead, Herbert Spencer's Principles of Psychology, 3rd edition (1872), and Sigmund Freud's Project for a Scientific Psychology (composed 1895) propounded connectionist or proto-connectionist theories. These tended to be speculative theories. But by the early 20th century, Edward Thorndike was experimenting on learning that posited a connectionist type network.

Friedrich Hayek independently conceived the Hebbian synapse learning model in a paper presented in 1920 and developed that model into global brain theory constituted of networks Hebbian synapses building into larger systems of maps and memory network. Hayek's breakthrough work was cited by Frank Rosenblatt in his perceptron paper.

Another form of connectionist model was the relational network framework developed by the linguist Sydney Lamb in the 1960s. Relational networks have been only used by linguists, and were never unified with the PDP approach. As a result, they are now used by very few researchers.

There are also hybrid connectionist models, mostly mixing symbolic representations with neural network models. The hybrid approach has been advocated by some researchers (such as Ron Sun).

Connectionism vs. computationalism debate

As connectionism became increasingly popular in the late 1980s, some researchers (including Jerry Fodor, Steven Pinker and others) reacted against it. They argued that connectionism, as then developing, threatened to obliterate what they saw as the progress being made in the fields of cognitive science and psychology by the classical approach of computationalism. Computationalism is a specific form of cognitivism that argues that mental activity is computational, that is, that the mind operates by performing purely formal operations on symbols, like a Turing machine. Some researchers argued that the trend in connectionism represented a reversion toward associationism and the abandonment of the idea of a language of thought, something they saw as mistaken. In contrast, those very tendencies made connectionism attractive for other researchers.

Connectionism and computationalism need not be at odds, but the debate in the late 1980s and early 1990s led to opposition between the two approaches. Throughout the debate, some researchers have argued that connectionism and computationalism are fully compatible, though full consensus on this issue has not been reached. Differences between the two approaches include the following:

  • Computationalists posit symbolic models that are structurally similar to underlying brain structure, whereas connectionists engage in "low-level" modeling, trying to ensure that their models resemble neurological structures.
  • Computationalists in general focus on the structure of explicit symbols (mental models) and syntactical rules for their internal manipulation, whereas connectionists focus on learning from environmental stimuli and storing this information in a form of connections between neurons.
  • Computationalists believe that internal mental activity consists of manipulation of explicit symbols, whereas connectionists believe that the manipulation of explicit symbols provides a poor model of mental activity.
  • Computationalists often posit domain specific symbolic sub-systems designed to support learning in specific areas of cognition (e.g., language, intentionality, number), whereas connectionists posit one or a small set of very general learning-mechanisms.

Despite these differences, some theorists have proposed that the connectionist architecture is simply the manner in which organic brains happen to implement the symbol-manipulation system. This is logically possible, as it is well known that connectionist models can implement symbol-manipulation systems of the kind used in computationalist models, as indeed they must be able if they are to explain the human ability to perform symbol-manipulation tasks. Several cognitive models combining both symbol-manipulative and connectionist architectures have been proposed, notably among them Paul Smolensky's Integrated Connectionist/Symbolic Cognitive Architecture (ICS). But the debate rests on whether this symbol manipulation forms the foundation of cognition in general, so this is not a potential vindication of computationalism. Nonetheless, computational descriptions may be helpful high-level descriptions of cognition of logic, for example.

The debate was largely centred on logical arguments about whether connectionist networks could produce the syntactic structure observed in this sort of reasoning. This was later achieved although using fast-variable binding abilities outside of those standardly assumed in connectionist models.

Part of the appeal of computational descriptions is that they are relatively easy to interpret, and thus may be seen as contributing to our understanding of particular mental processes, whereas connectionist models are in general more opaque, to the extent that they may be describable only in very general terms (such as specifying the learning algorithm, the number of units, etc.), or in unhelpfully low-level terms. In this sense connectionist models may instantiate, and thereby provide evidence for, a broad theory of cognition (i.e., connectionism), without representing a helpful theory of the particular process that is being modelled. In this sense the debate might be considered as to some extent reflecting a mere difference in the level of analysis in which particular theories are framed. Some researchers suggest that the analysis gap is the consequence of connectionist mechanisms giving rise to emergent phenomena that may be describable in computational terms.

The recent popularity of dynamical systems in philosophy of mind have added a new perspective on the debate; some authors now argue that any split between connectionism and computationalism is more conclusively characterized as a split between computationalism and dynamical systems.

In 2014, Alex Graves and others from DeepMind published a series of papers describing a novel Deep Neural Network structure called the Neural Turing Machine able to read symbols on a tape and store symbols in memory. Relational Networks, another Deep Network module published by DeepMind, are able to create object-like representations and manipulate them to answer complex questions. Relational Networks and Neural Turing Machines are further evidence that connectionism and computationalism need not be at odds.

Computational theory of mind

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https://en.wikipedia.org/wiki/Computational_theory_of_mind

In philosophy of mind, the computational theory of mind (CTM), also known as computationalism, is a family of views that hold that the human mind is an information processing system and that cognition and consciousness together are a form of computation. Warren McCulloch and Walter Pitts (1943) were the first to suggest that neural activity is computational. They argued that neural computations explain cognition. The theory was proposed in its modern form by Hilary Putnam in 1967, and developed by his PhD student, philosopher, and cognitive scientist Jerry Fodor in the 1960s, 1970s, and 1980s. Despite being vigorously disputed in analytic philosophy in the 1990s due to work by Putnam himself, John Searle, and others, the view is common in modern cognitive psychology and is presumed by many theorists of evolutionary psychology. In the 2000s and 2010s the view has resurfaced in analytic philosophy (Scheutz 2003, Edelman 2008).

The computational theory of mind holds that the mind is a computational system that is realized (i.e. physically implemented) by neural activity in the brain. The theory can be elaborated in many ways and varies largely based on how the term computation is understood. Computation is commonly understood in terms of Turing machines which manipulate symbols according to a rule, in combination with the internal state of the machine. The critical aspect of such a computational model is that we can abstract away from particular physical details of the machine that is implementing the computation. For example, the appropriate computation could be implemented either by silicon chips or biological neural networks, so long as there is a series of outputs based on manipulations of inputs and internal states, performed according to a rule. CTM, therefore holds that the mind is not simply analogous to a computer program, but that it is literally a computational system.

Computational theories of mind are often said to require mental representation because 'input' into a computation comes in the form of symbols or representations of other objects. A computer cannot compute an actual object, but must interpret and represent the object in some form and then compute the representation. The computational theory of mind is related to the representational theory of mind in that they both require that mental states are representations. However, the representational theory of mind shifts the focus to the symbols being manipulated. This approach better accounts for systematicity and productivity. In Fodor's original views, the computational theory of mind is also related to the language of thought. The language of thought theory allows the mind to process more complex representations with the help of semantics. (See below in semantics of mental states).

Recent work has suggested that we make a distinction between the mind and cognition. Building from the tradition of McCulloch and Pitts, the computational theory of cognition (CTC) states that neural computations explain cognition. The computational theory of mind asserts that not only cognition, but also phenomenal consciousness or qualia, are computational. That is to say, CTM entails CTC. While phenomenal consciousness could fulfill some other functional role, computational theory of cognition leaves open the possibility that some aspects of the mind could be non-computational. CTC therefore provides an important explanatory framework for understanding neural networks, while avoiding counter-arguments that center around phenomenal consciousness.

"Computer metaphor"

Computational theory of mind is not the same as the computer metaphor, comparing the mind to a modern-day digital computer. Computational theory just uses some of the same principles as those found in digital computing. While the computer metaphor draws an analogy between the mind as software and the brain as hardware, CTM is the claim that the mind is a computational system. More specifically, it states that a computational simulation of a mind is sufficient for the actual presence of a mind, and that a mind truly can be simulated computationally.

'Computational system' is not meant to mean a modern-day electronic computer. Rather, a computational system is a symbol manipulator that follows step-by-step functions to compute input and form output. Alan Turing describes this type of computer in his concept of a Turing machine.

Early proponents

One of the earliest proponents of the computational theory of mind was Thomas Hobbes, who said, "by reasoning, I understand computation. And to compute is to collect the sum of many things added together at the same time, or to know the remainder when one thing has been taken from another. To reason therefore is the same as to add or to subtract." Since Hobbes lived before the contemporary identification of computing with instantiating effective procedures, he cannot be interpreted as explicitly endorsing the computational theory of mind, in the contemporary sense.

Causal picture of thoughts

At the heart of the computational theory of mind is the idea that thoughts are a form of computation, and a computation is by definition a systematic set of rules for the relations among representations. This means that a mental state represents something if and only if there is some causal correlation between the mental state and that particular thing. An example would be seeing dark clouds and thinking "clouds mean rain", where there is a correlation between the thought of the clouds and rain, as the clouds causing rain. This is sometimes known as natural meaning. Conversely, there is another side to the causality of thoughts and that is the non-natural representation of thoughts. An example would be seeing a red traffic light and thinking "red means stop", there is nothing about the color red that indicates it represents stopping, and thus is just a convention that has been invented, similar to languages and their abilities to form representations.

Semantics of mental states

The computational theory of mind states that the mind functions as a symbolic operator, and that mental representations are symbolic representations; just as the semantics of language are the features of words and sentences that relate to their meaning, the semantics of mental states are those meanings of representations, the definitions of the 'words' of the language of thought. If these basic mental states can have a particular meaning just as words in a language do, then this means that more complex mental states (thoughts) can be created, even if they have never been encountered before. Just as new sentences that are read can be understood even if they have never been encountered before, as long as the basic components are understood, and it is syntactically correct. For example: "I have eaten plum pudding every day of this fortnight." While it's doubtful many have seen this particular configuration of words, nonetheless most readers should be able to glean an understanding of this sentence because it is syntactically correct and the constituent parts are understood.

Criticism

A range of arguments have been proposed against physicalist conceptions used in computational theories of mind.

An early, though indirect, criticism of the computational theory of mind comes from philosopher John Searle. In his thought experiment known as the Chinese room, Searle attempts to refute the claims that artificially intelligent agents can be said to have intentionality and understanding and that these systems, because they can be said to be minds themselves, are sufficient for the study of the human mind. Searle asks us to imagine that there is a man in a room with no way of communicating with anyone or anything outside of the room except for a piece of paper with symbols written on it that is passed under the door. With the paper, the man is to use a series of provided rule books to return paper containing different symbols. Unknown to the man in the room, these symbols are of a Chinese language, and this process generates a conversation that a Chinese speaker outside of the room can actually understand. Searle contends that the man in the room does not understand the Chinese conversation. This is essentially what the computational theory of mind presents us—a model in which the mind simply decodes symbols and outputs more symbols. Searle argues that this is not real understanding or intentionality. This was originally written as a repudiation of the idea that computers work like minds.

Searle has further raised questions about what exactly constitutes a computation:

the wall behind my back is right now implementing the WordStar program, because there is some pattern of molecule movements that is isomorphic with the formal structure of WordStar. But if the wall is implementing WordStar, if it is a big enough wall it is implementing any program, including any program implemented in the brain.

Objections like Searle's might be called insufficiency objections. They claim that computational theories of mind fail because computation is insufficient to account for some capacity of the mind. Arguments from qualia, such as Frank Jackson's knowledge argument, can be understood as objections to computational theories of mind in this way—though they take aim at physicalist conceptions of the mind in general, and not computational theories specifically.

There are also objections which are directly tailored for computational theories of mind.

Putnam himself (see in particular Representation and Reality and the first part of Renewing Philosophy) became a prominent critic of computationalism for a variety of reasons, including ones related to Searle's Chinese room arguments, questions of world-word reference relations, and thoughts about the mind-body relationship. Regarding functionalism in particular, Putnam has claimed along lines similar to, but more general than Searle's arguments, that the question of whether the human mind can implement computational states is not relevant to the question of the nature of mind, because "every ordinary open system realizes every abstract finite automaton." Computationalists have responded by aiming to develop criteria describing what exactly counts as an implementation.

Roger Penrose has proposed the idea that the human mind does not use a knowably sound calculation procedure to understand and discover mathematical intricacies. This would mean that a normal Turing complete computer would not be able to ascertain certain mathematical truths that human minds can.

Pancomputationalism

Supporters of CTM are faced with a simple yet important question whose answer has proved elusive and controversial: what does it take for a physical system (such as a mind, or an artificial computer) to perform computations? A very straightforward account is based on a simple mapping between abstract mathematical computations and physical systems: a system performs computation C if and only if there is a mapping between a sequence of states individuated by C and a sequence of states individuated by a physical description of the system.

Putnam (1988) and Searle (1992) argue that this simple mapping account (SMA) trivializes the empirical import of computational descriptions. As Putnam put it, “everything is a Probabilistic Automaton under some Description”.  Even rocks, walls, and buckets of water—contrary to appearances—are computing systems. Gualtiero Piccinini identifies different versions of Pancomputationalism.

In response to the trivialization criticism, and to restrict SMA, philosophers of mind have offered different accounts of computational systems. These typically include causal account, semantic account, syntactic account, and mechanistic account. Instead of a semantic restriction, the syntactic account imposes a syntactic restriction. The mechanistic account was first introduced by Gualtiero Piccinini in 2007.

Prominent scholars

  • Daniel Dennett proposed the multiple drafts model, in which consciousness seems linear but is actually blurry and gappy, distributed over space and time in the brain. Consciousness is the computation, there is no extra step or "Cartesian theater" in which you become conscious of the computation.
  • Jerry Fodor argues that mental states, such as beliefs and desires, are relations between individuals and mental representations. He maintains that these representations can only be correctly explained in terms of a language of thought (LOT) in the mind. Further, this language of thought itself is codified in the brain, not just a useful explanatory tool. Fodor adheres to a species of functionalism, maintaining that thinking and other mental processes consist primarily of computations operating on the syntax of the representations that make up the language of thought. In later work (Concepts and The Elm and the Expert), Fodor has refined and even questioned some of his original computationalist views, and adopted a highly modified version of LOT (see LOT2).
  • David Marr proposed that cognitive processes have three levels of description: the computational level (which describes that computational problem (i.e., input/output mapping) computed by the cognitive process); the algorithmic level (which presents the algorithm used for computing the problem postulated at the computational level); and the implementational level (which describes the physical implementation of the algorithm postulated at the algorithmic level in biological matter, e.g. the brain). (Marr 1981)
  • Ulric Neisser coined the term 'cognitive psychology' in his book published in 1967 (Cognitive Psychology), wherein Neisser characterizes people as dynamic information-processing systems whose mental operations might be described in computational terms.
  • Steven Pinker described a "language instinct," an evolved, built-in capacity to learn language (if not writing).
  • Hilary Putnam proposed functionalism to describe consciousness, asserting that it is the computation that equates to consciousness, regardless of whether the computation is operating in a brain, in a computer, or in a "brain in a vat."
  • Georges Rey, professor at the University of Maryland, builds on Jerry Fodor's representational theory of mind to produce his own version of a Computational/Representational Theory of Thought.

 

Operator (computer programming)

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