According to some, Niobe is the goddess of snow and winter, whose children, slain by Apollo and Artemis, symbolize the ice and snow melted by the sun in spring; according to others, she is an earth-goddess, whose progeny - vegetation and the fruits of the soil - is dried up and slain every summer by the shafts of the sun-god. Burmeister regards the legend as an incident in the struggle between the followers of Dionysus and Apollo in Thebes, in which the former were defeated and driven back to Lydia. Heffter builds up the story round the dripping rock in Lydia, really representing an Asiatic goddess, but taken by the Greeks for an ordinary woman. Enmann, who interprets the name as "she who prevents increase" (in contrast to Leto, who made women prolific), considers the main point of the myth to be Niobe's loss of her children. He compares her story with that of Lamia, who, after her children had been slain by Zeus, retired to a lonely cave and carried off and killed the children of others. The appearance of the rock on Sipylus gave rise to the story of Niobe having been turned to stone. The tragedians used her story to point the moral of the instability of human happiness; Niobe became the representative of human nature, liable to pride in prosperity and forgetfulness of the respect and submission due to the gods.