Paul Hindemith is best known as a composer, but was also a violinist, violist, conductor, and teacher who wrote a series of textbooks on musicianship, harmony, and composition. Apparently, even back in the ’40’s, he felt that many musicians lacked a sufficient understanding of the underlying principles which make music work.
In his preface to Elementary Training for Musicians he writes:
“If our performers – players, singers, and conductors alike – had a better insight into the essentials of musical scores, we would not be faced with what seems to have become almost a rule in the superficially over-polished performances of today: either the rattling through of a piece without any reasonable articulation, without any deeper penetration into its character, tempo, expression, meaning, and effect – or the hyper-individualistic distortion of the ideas expressed in a composer’s score.”
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