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- What makes an interval “Perfect”? 14 answers
Why are 2nds, 3rds, 6ths, and 7ths major or minor, but 4ths, and 5ths are diminished, augmented, or perfect? I might have some of that a little mixed up and I realize some are enharmonic equivalents.
This is, I suppose, more an etymological question than a pure music theory but I thought this might be the right place to ask.