 Líf and Lífþrasir are mentioned in the "Poetic Edda", compiled in the thirteenth century from earlier traditional sources, and the "Prose Edda", written in the 13th century by Snorri Sturluson.Many scholars have speculated as to the underlying meaning and origins of the two names.In the poem "Vafþrúðnismál", collected in the "Poetic Edda", the god Odin poses a question to the jötunn Vafþrúðnir, asking who among mankind will survive when the winter at the end of the world Fimbulvetr occurs.