Who is Lyman Fowler from The Man Who Listens to Horses and what is their importance?

Lyman Fowler was one of Monty's teachers in high school. When Fowler assigns his students an essay in which they are to write about their dreams, Monty writes about his desire to own a thoroughbred training facility. Fowler gives Monty an F on his essay and tells him that he shouldn't be writing about unattainable dreams. The teacher later learns about his facility and visits him there. Lyman apologizes and admits he was wrong.