Willa Cather said this quote

He had never got so much back for himself from any pupil as he did from Miss Kronborg. From the first she had stimulated him; something in her personality invariably affected him. Now that he was feeling his way toward her voice, he found her more interesting than ever before. She lifted the tedium of the winter for him, gave him curious fancies and reveries. Musically, she was sympathetic to him. Why this was true, he never asked himself. He had learned that one must take where and when one can the mysterious mental irritant that rouses one's imagination; that it is not to be had by order. She often wearied him, but she never bored him.