Many tales intertwine the lives of Aditi and Vishnu. Since Hindu culture believes strongly in reincarnation, the relationship between the two depends greatly on which incarnation, or avatar, each is portraying in the story being told. In some, Aditi is Vishnu's mother (in his avatars as Vamana and Krishna), in others she is his lover, and in yet others Aditi and Vishnu are considered the same diety.
