Feldenkrais on sensitivity.

”Now, in order to have free choice we must have a significant difference. And in order to have a significant difference, you cannot increase the stimulus, but you can increase your sensitivity. And since sensitivity increases only when you reduce the stimulus, that means you reduce the effort. Therefore, anything that you learn with difficulty, with pain, with strain is futile; you will never use it in life.”

—Moshe Feldenkrais, ”The Master Moves”