"There are some who call my order the knights of the mind," Luwin replied. "You are a surpassing clever boy when you work at it, Bran. Have you ever thought that you might wear a maester's chain? There is no limit to what you might learn."--George R.R. Martin, A Game of Thrones
"I want to learn magic," Bran told him. "The crow promised me I would fly."
Maester Luwin sighed. "I can teach you history, healing, herblore. I can teach you the speech of ravens, and how to build a castle, and the way a sailor steers his ship by the stars. I can teach you to measure the days and mark the seasons, and a thousand things more. But, Bran, no man can teach you magic."