There is a world outside the one we know,” he said....

“ There is a world outside the one we know,” he said softly, “with cultures and races and armies who have never heard of us. Yes, and cities greater than Yenking and Karakorum. To survive, to grow, we must remain strong. We must conquer new lands, so that our army is always fed, always moving. To stop is to die, Chagatai. ”

Conn Iggulden

From : Khan: Empire of Silver