by which he "evolved" from a single being into this multiplicity of elements. The process began when Atum appeared on the mound and gave rise to the air god Shu and his sister Tefnut, whose existence represented the emergence of space amid the waters. To explain how Atum did this, the myth uses the metaphor of masturbation, with the hand he used in this act representing the female principle inherent within him. He is also said to have "sneezed" and "spat" to produce Shu and Tefnut, a metaphor that arose from puns on their names. Next, Shu and Tefnut coupled to produce the earth god Geb and the sky goddess Nut, who defined the limits of the world. Geb and Nut in turn gave rise to four children, who represented the forces of life: Osiris, god of fertility and regeneration; Isis, goddess of motherhood; Set, the god of chaos; and Nephthys, the goddess of protection. The myth thus represented the process by which life was made possible. These nine gods were grouped theologically as the Ennead, but the eight lesser gods, and all other things in the world, were ultimately seen as extensions of Atum. Memphis The Memphite version of creation centered on Ptah, who was the patron god of craftsmen. As such, he represented the craftsman's ability to envision a finished product, and shape raw materials to create that product. The Memphite theology said that Ptah similarly created the world. This, unlike the other Egyptian creations, was not a physical but an intellectual creation by the Word and the Mind of God. The ideas developed within Ptah's heart (regarded by the Egyptians as the seat of human thought) were given form when he named them with his tongue. By speaking these names, Ptah produced the gods and all other things. The Memphite creation myth coexisted with that of Heliopolis, as Ptah's creative thought and speech were believed to have caused the formation of Atum and the Ennead. Ptah was also associated with Tatjenen, the god who personified the pyramidal mound. Thebes Theban theology claimed that Amun was not merely a member of the Ogdoad, but the hidden force behind all things. There is a conflation of all notions of creation into the personality of Amun, a synthesis which emphasizes how Amun transcends all other deities in his being "beyond the sky and deeper than the underworld". One Theban myth