"You can learn," agreed Xat-Cerxis. "Hold some string! Watch my fingers. Watch shape. I will tie and you will follow." Slowly, Xat-Cerxis made some loops and then tightened them up by pulling on the edge of the thread. They made a simple knot. "One, two, three, four, five!" she counted as more tiny knots appeared. "Imagine every knot is a llama! We have five llamas! It is good to keep track," she said as if that explained everything about her counting system.