List of motets by Johann Sebastian Bach

It is not known how many motets Johann Sebastian Bach composed, because some have probably gone missing, and there are a few doubtful attributions among the surviving ones associated with him. There are six authenticated motets catalogued BWV 225–230. BWV 228 appears to have been written at Weimar, between 1708 and 1717, and the other five in Leipzig, between 1723 and 1727. A seventh motet, Ich lasse dich nicht, BWV Anh. 159, which was formerly attributed to Bach's older cousin Johann Christoph Bach, appears to be one of Bach's earlier works, possibly composed during the Weimar period.

Several of the motets were written for funerals. There is some uncertainty as to the extent that motets would have been called for in normal church services - there is evidence that it was considered an archaic form. The text of Jauchzet dem Herrn, alle Welt, BWV Anh. 160 (whether or not the piece is attributable to Bach) suggests a performance at Christmas. Another possible use is the suggestion of the scholar Christoph Wolff that some of the choral writing in the motets for example Singet dem Herrn ein neues Lied, would have been useful for training Bach's young singers.

Surname

A surname or family name is a name added to a given name. In many cases, a surname is a family name and many dictionaries define "surname" as a synonym of "family name". In the western hemisphere, it is commonly synonymous with last name because it is usually placed at the end of a person's given name.

In most Spanish-speaking and Portuguese-speaking countries, two or more last names (or surnames) may be used. In China, Hungary, Japan, Korea, Madagascar, Taiwan, Vietnam, and parts of India, the family name is placed before a person's given name.

The style of having both a family name (surname) and a given name (forename) is far from universal. In many countries, it is common for ordinary people to have only one name or mononym.

The concept of a "surname" is a relatively recent historical development, evolving from a medieval naming practice called a "byname". Based on an individual's occupation or area of residence, a byname would be used in situations where more than one person had the same name.

Context-sensitive language

In theoretical computer science, a context-sensitive language is a formal language that can be defined by a context-sensitive grammar (and equivalently by a noncontracting grammar). That is one of the four types of grammars in the Chomsky hierarchy.

Computational properties

Computationally, a context-sensitive language is equivalent with a linear bounded nondeterministic Turing machine, also called a linear bounded automaton. That is a non-deterministic Turing machine with a tape of only kn cells, where n is the size of the input and k is a constant associated with the machine. This means that every formal language that can be decided by such a machine is a context-sensitive language, and every context-sensitive language can be decided by such a machine.

This set of languages is also known as NLINSPACE or NSPACE(O(n)), because they can be accepted using linear space on a non-deterministic Turing machine. The class LINSPACE (or DSPACE(O(n))) is defined the same, except using a deterministic Turing machine. Clearly LINSPACE is a subset of NLINSPACE, but it is not known whether LINSPACE=NLINSPACE.

Bach (journal)

Bach is a biannual peer-reviewed academic journal published by the Riemenschneider Bach Institute (Baldwin Wallace University). It covers the study of Johann Sebastian Bach and Baroque music. The journal was established in 1970 and the editor-in-chief is Melvin Unger (Baldwin Wallace University).

External links