Köchel catalogue Köchel catalogue The Köchel catalogue () is a chronological catalogue of compositions by Wolfgang Amadeus Mozart, originally created by Ludwig von Köchel, in which the entries are abbreviated "K." and "KV". The numbers of the Köchel catalogue reflect the continuing establishment of a complete chronology of Mozart's works, and provide a shorthand reference to the compositions. According to Köchel's counting, "Requiem in D minor" is the 626th piece Mozart composed, thus is designated either "K. 626" or "KV 626"; however, his original catalogue (1862) of Mozart has been twice revised, and some works have had three KV. numbers, e.g. Mozart's
19th-century philosophy physical and empirical and is only realized through the individual's intuition, rather than through the doctrines of established religions. "Social Darwinism" refers to theories that apply the evolutionary concept of natural selection to human society. 19th-century philosophy In the 19th century, the philosophies of the Enlightenment began to have a dramatic effect, the landmark works of philosophers such as Immanuel Kant and Jean-Jacques Rousseau influencing new generations of thinkers. In the late 18th century a movement known as Romanticism began; it validated strong emotion as an authentic not of aesthetic experience, placing new emphasis on such emotions as trepidation, horror