It is a remarkable statement, but, nevertheless, true, that all the investigations of the modern scientists, aided by the laryngoscope, did not yield any other results than a confirmation of the correctness of the principles adopted and taught by the old Italian masters.

Not knowing anything about the anatomy of the throat or the laryngoscope, which is a modern invention, they were enabled by superior intelligence, a refined sense of beauty, aided and supported by an infallible ear. Mme. Lilli Lehmann, of world-wide reputation, said to me: "The ear is the best existing teacher." And if one thinks it over for a minute, by means of what else but the ear does the teacher judge the student's faults or virtues? Therefore, let the student learn to listen to himself from the very beginning. He or she should not glue his or her eyes to the teacher's face, trying to read his thoughts, but should endeavor to hear him—or herself, and educate the ear by comparing personal impressions with those made of the teacher. 

—The Etude, January 1, 1914