while the balancing of figures on many Greek reliefs—especially on Attic funerary stelæ—illustrates symmetry (_cf._ Fig. 75). Pliny characterizes certain artists by their success in effecting symmetry and rhythm. Thus Myron surpassed Polykleitos in being more rhythmic and in paying more attention to symmetry.[584] He says that Lysippos most diligently preserved symmetry by bringing unthought-of innovations into the square canon of earlier artists.[585] Parrhasios was the first to introduce symmetry into painting.[586] Diogenes Laertios says that the sculptor Pythagoras was the first to aim at rhythm as well as symmetry.[587] In all such passages it is clear that canons of proportion are meant. The doctrine of human proportions is very ancient, originating in Egyptian art.[588] It appears early in Greek architecture in the proportions of columns and other members of a temple,[589] and it was soon transferred to sculpture. As Greek sculpture evolved on traditional lines,[590] we should assume that it paid attention to the doctrine of proportions in the human figure, based on numerical ratios, and that such a doctrine would vary from age to age in the various schools of sculpture. Such an assumption is borne out by both literary and archæological evidence. Toward the end of Hellenism many writers refer to just such a measured basis of proportion in Greek art.[591] Archæologists have shown by the careful study of multitudes of statues that such proportions exist in Greek sculpture. Thus A. Kalkmann[592] has proved that there are sets of ratios in the treatment of the face used by successive schools of sculpture, which were canonical, whether formulated or not. G. Fritsch[593] has done for the whole body what Kalkman has done for the face. In fact, anthropometry in relation to Greek sculpture has now become an exact science.[594]