Theory without practice is of ...

Theory without practice is of little value, whereas practice is the proof of theory.Theory is the knowledge, practice the ability.
 Alois Podhajsky

Quotes from the same author

There is one principle that should never be abandoned, namely, that the rider must learn to control himself before he can control his horse. This is the basic, most important principle to be preserved in equitation.
 Alois Podhajsky
The objective of the Classical Art of Riding is to train the horse not only to be brilliant in the movements and the exercises of the High School but also to be quiet, supple and obedient and by his smooth movements to make riding a true pleasure
 Alois Podhajsky