"[Callas was] An outstanding historical figure, ranking with Malibran, Viardot, Toscanini, and Mahler. She is somewhat like Viardot, Chorley's "tones of an engaging tenderness" mingled with those "of a less winning quality." It was a flawed voice. But then Callas sought to capture in her singing not just beauty but a whole humanity, and within her system, the flaws feed the feeling, the sour plangency and the strident defiance becoming aspects of the canto. They were literally defects of her voice; she bent them into advantages of her singing. [Her voice] is what she had. What she made was a musical information of what was happening to her characters, a searching virtuosity. Suffering, delight, humility, hubris, despair, rhapsody — all this was musically appointed, through her use of the voice flying the text upon the notes...."