The Mane Event: Pedagogy between a trainer and a horse

10 years ago, my first principal at my first school in Surrey used to utter a proverb. The old adage "you can lead a horse to water but you can't make them drink" was often spoken by him to many that he worked with. 

He used to finish it up with the question:

"....so how do you make the horse drink?” leaving me at a loss. 

He would shortly thereafter provide the answer: "Salt the oats."