Without a doubt Pryso, and to think, he never learned how to read music.
I have personally known a few remarkable musicians who never learned how to read music. They took that statement to mean it's not necessary to read music in order to become a musician.
I have no idea what it takes to become a musician, but some of the worst musicians even have a degree in music. Personally, it's my opinion that some got it, and some don't got it; meaning it's a natural talent. Having said that, people who went to school and can read music will be more successful.
Here is Errol Garner's most famous tune;
https://www.youtube.com/watch?v=P_tAU3GM9XI
And my favorite version;
https://www.youtube.com/watch?v=OQ-JgK9h_MU