The Wisdom of Doing Less

"Do a little less than your utmost while learning... continuing to do a little less than your utmost, you go on improving.... The wisdom of doing a little less than one really can pushes the record of achievement further and further as you come nearer to it, similar to the horizon that recedes on approaching it." 

This is Chapter 20 from Feldenkrais Illustrated: The Art of Learning, excerpts from the writings of Moshe Feldenkrais, edited and illustrated by Tiffany Sankary.