Henry G: "Maybe most shifts in style depend on a new sense of decorum. That is, if there's a fitness in relation to experience or reality, then, as our general sense of reality changes, the old styles or old forms of decorum will no longer ring true. (Maybe some forms of decorum never change, though - built as they are on our direct responses to certain basic kinds of experiences. Laughter in comedy is just a special application of humor in general.)"