Although definitions of music vary wildly throughout the world, every known culture partakes in it, and it 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 theories have been proposed by scholars from a wide range of disciplines, though none has achieved broad 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 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. Such interaction led to the Tang dynasty's music being heavily influenced by Central Asian traditions, while the Tang dynasty's music, the Japanese gagaku and Korean court music each influenced each other. Historically, religions have often been catalysts for music. The Vedas of Hinduism immensely influenced Indian classical music, and the Five Classics of Confucianism laid the basis for subsequent Chinese music. Following the rapid spread of Islam in the 7th 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 popular music. Source: Wikipedia (en)