To help us understand Thelonious Monk's chord progressions, and specifically why they're so hard to improvise over, let’s make a musical experiment involving chords and improvisation.

With our right hand, let’s play the melody to "Twinkle, Twinkle Little Star":

Next, we’ll add the song's basic harmonies in our left hand:

We have a nice melody, and chords that support the melody and would also be easy to improvise over.

Now, let’s reharmonize the melody. We’ll have some fun and intentionally use some chords that are unexpected, to give the melody a whole new flavor:

So far so good. But what happens when we try to improvise over these new, colorful melodies?

Go ahead, give it a try. (I’ll wait.)

Hmmm…. Not so easy, is it?

This process is exactly what Monk did in many of his tunes. He'd compose a melody that sounded catchy and tuneful. But then he'd harmonize that melody in unique ways. These chords sound great with the melody, and give a "Monk-ish" flavor to the tune, even when the melody is essentially diatonic or even consisting of repeated notes.

But when we take those same chords as the starting point for our improvisations, and try to navigate those changes while creating spontaneous melodic lines, we quickly find out how challenging it is.

If you'd like to watch me demonstrate this on one of Monk's greatest tunes, check this out:

I hope this gives you some insight not only on the challenge of playing Thelonious Monk's music, but some insight into a way to approach his great compositions for yourself.

Enjoy the journey, and "let the music flow!"

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