Blues as a musical term can describe an oral tradition of African American poetry set to music using blues form (typically three-line stanzas with the first two lines being similar, set to a twelve-bar harmonic framework called a blues progression); the form of the poetry and/or the music; and an aesthetic that remains an ideal for Jazz performance in general. Blues originated as an expression of the individual and interactive social tradition of a displaced African American population. It began with the African American agrarian working class of the Mississippi Delta and combined African American and European American traditions, particularly hollers (field work songs) and British ballads. Only after blues was well established did it broaden to include the white middle class and function as a form of entertainment. In fact, Black Gospel music, which is very popular among religious African Americans, has its roots in Blues as a genre.
In my opinion, Blues has "soul". It can evoke deep feelings and emotions that can deeply affect a person, depending on the source and content of a particular Blues tune. Having listened extensively to Black Gospel music, both upbeat and "blues" in nature, I can personally attest to its transforming power in changing a person from within. I highly recommend both Blues music in general as a genre, and also Black Gospel music in particular which derives a lot of its material from Blues, and indeed vice versa as well.
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All the best,
Mike
[This message has been edited by keybplayer (edited 05-25-2009).]