Question: Who is reported in some ancient sources to have been a philosopher who was the earliest Greek to develop the theory of atomism, who had a daughters were sought by he jealous murderer of Castor? 
Sentence (from "Erinna"): Erinna is best known for her long poem, the "Distaff", a three-hundred line hexameter lament for her childhood friend Baucis, who had died shortly after marriage.
Relevant evidence: No