"The aim of art, so far as one can speak in art of an aim at all, has always been the same; the melting together of material gained in experience in life with the natural qualities of the medium. The medium swings and resonates as one strikes its strings and as one masters its registers and stops.

For every medium possesses its own rhythmic laws, and thus its strict limitations through which it is distinguished as the specific way of expression that it is. The limitation of the medium is an essential condition for the quality in a work of art, for the boundlessness of the spirit can only find material expression within the lawful limits of a medium . . . "