📜 Simms, Bryan R. 1986. Music of the twentieth century: style and structure. New York: Schirmer Books
As to be expected from the book's subtitle and its place in the current "peripheral" wiki section, the reviewed work is not directly related to music games. Introduction casts doubt if the wiki-related matter will appear at all, because we are promised that "music will be our ultimate guide". Does it mean what is being heard? What is being written? Both options don't fare well for our areas of music. The following engagement with musical examples (which actually start quite far in the 19th century) is a standard stuff focused on pitch classes and the technique of variation. Spoiler alert, there is a chapter called Indeterminacy, but let's now have a look at an earlier part.
After WWI
The first notable detail of the book relates to the period right after World War I. The author presents a clear-cut picture of mainstream music scene: total dominance of neo-classicism, a view provided with a historical socio-psychological interpretation (a reaction to the war), as explained:
Experimentation became much less important to the mainstream of musical development and was confined instead to outlying regions such as the United States or to the dilettantish activities of Dadaism and Futurism3
This statement might be common outside of our "bubble", but it is characteristic when contrasted with the literature that focuses on more game-related areas, where the developments swept under the rag in the quote above, are usually more exposed and treated with more reverence.
After WWII
#Innovation paradigm
Music is based on creativity. It is not good if it only repeats what already has been done before. Break the boundaries! New ideas and originality are key things to praise in all arts.
When the chapter 13. Indeterminacy comes, it is quite unremarkable, the previous mode of analysis is gone and it's as if an invisible switch was set now to an #innovation paradigm. A positive technical distinction is keeping "indeterminacy of composition" and "indeterminacy of performance" as separate. In this part of the text the traditions of experimental music and avant-garde which got a separate chapters 11 and 12 as "Experimental music in America" and "The revival of the avant-garde" are now considered together. But that terminological imprecision is not noticeable, as the content is now dominated for quite some time by John Cage, then a considerable focus is given to Pierre Boulez and Karlheinz Stockhausen, and then other innovators may find a single paragraph, or two, for themselves.
After a break for electronics, in chapter 15 about "recent" music, threads of indeterminacy reappear, like In C and activities of Fluxus. In general, it is clear that the author is not extremely passionate about what would be the most interesting from the perspective of this wiki. But it seems like due diligence in providing a basic description of this part of the developments of 20th century music is properly done.
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