Let us note also that when an art becomes detached from its own past, when it is not based on natural human life, and does not obey those general laws to which all art is subject, it is sure to evolve conventions of one sort or another and to become artificial. This is to be observed in what is called the “rococo” style of architecture, as well as in the terrible objects perpetrated by the “futurists” and “cubists” (anything that is of the future must also be of the past, no matter whether it is a picture, or a tree, or an idea). Opera was soon in the grip of these conventions from which, with a few notable exceptions, it has never escaped. Even the common conventions of the drama, which we accept readily enough, are in opera stretched to the breaking point. For many generations operas were planned according to a set, inflexible scheme of acts; a woman took a man’s part (as in Gounod’s “Faust”); characters were stereotyped; the position of the chief _aria_ (solo) for the prima donna was exactly determined so as to give to her entrance all possible impressiveness; the set musical pieces (solos, duets, choruses, and so forth) were arranged artificially and not to satisfy any dramatic necessity. There is some justness in Wagner’s saying that the old conventional opera was “a concert in costume.” An example of this conventionality and lack of dramatic unity may be found in the famous quartette scene in Verdi’s “Rigoletto,” an opera which is typical of the Italian style (in which, in Meredith’s phrase, “there is much dallying with beauty in the thick of sweet anguish”). In this scene there are two persons in hiding to watch two others. The concealment is the hinge upon which, for the moment, the story swings. But the exigencies of the music are such that, before the piece has progressed very far, all four are singing at the top of their lungs and with no pretext of concealment--in a charming piece of music, indeed, but quite divested of dramatic truth and unity. And then, naturally enough, the thin veneer of drama having been pierced, they answer your applause by joining hands and bowing, after which the two conceal themselves again, the music strikes up as before, and the whole scene is repeated.