In our latest podcast episode "The Science of Necrophilia," we focus in large part on necrophilia among animals and the psychological complexities of human necrophilia. We did not, however, dive much into the topic's mythic depths.
For humans, the notion of sex with the dead summons a number of powerful themes, but let's consider mortality itself. Sexual reproduction is ever the genetic mission for any organism, and death serves as the ultimate closure for that particular from of life-beyond-death. So tales of lovers brought back from death (such as Sleeping Beauty) are all necrophilic in their own way.
Take the Ancient Egyptian myth of Isis and Osiris. The god Osiris is murdered by his usurper brother Set -- and not just murdered, but torn to scattered pieces by Set's monster form. His widow Isis, a potent sorcerer, then gathers the many fragments of her dead husband, pieces them together and resurrects his body just long enough to conceive a child with him. Isis' belly swells and Osiris descends into the underworld, where he becomes lord of the dead. The child of their union becomes Horus, the god of kings for ages to follow.
It's an especially interesting myth when we take into account the "functional necrophilia" of the Amazonian frog Rhinella proboscidea and the human practices of posthumous egg & sperm retrieval, which essentially allows a living human to breed with the dead.
Once more, myth influences our culture, science grows out of culture, and science makes myth reality.