6dc5455c____The_Coppermind___17th_Shard__Entry
[Chapter] 25 [Entry] 
The Balance. Is it real? We've almost forgotten this little bit of lore. Skaa used to talk about it, before the Collapse. Philosophers discussed it a great deal in the third and fourth centuries, but by Kelsier's time, it was mostly a forgotten topic. But it was real. There was a physiological difference between skaa and nobility. When the Lord Ruler altered mankind to make them more capable of dealing with ash, he changed other things as well. Some groups of people—the noblemen—were created to be less fertile, but taller, stronger, and more intelligent. Others—the skaa—were made to be shorter, hardier, and to have many children. The changes were slight, however, and after a thousand years of interbreeding, the differences had largely been erased.
The Hero of Ages/Epigraphs - The Coppermind - 17th Shard
Entry