Jazz theory: 2 5 1 chord progression

[mijulan]

In Jazz, I understand that the 2 5 1 chord progression is the most important. Why is this? Why not use other progressions?

[lelle]

I think the short answer is simply tradition. It's a strong progression that pops up everywhere in western music (it's very common in classical as well), so it simply seems like culturally, our ears have learned to enjoy that progression. The root of each subsequent chord descends a fifth, which creates a strong harmonic movement (it's similar to descending the circle of fifths), and you can vary and alter the chords in many ways while building on the fundamental progression (this is true for many other chord progressions too).

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