“I asked why each link was a different metal. A silver chain would look much finer with his grey robes, I said. Maester Luwin laughed. A maester forges his chain with study, he told me. The different metals are each a different kind of learning, gold for the study of money and accounts, silver for healing, iron for warcraft. And he said there were other meanings as well. The collar is supposed to remind a maester of the realm he serves, isn’t that so? Lords are gold and knights steel, but two links can’t make a chain. You also need silver and iron and lead, tin and copper and bronze and all the rest, and those are farmers and smiths and merchants and the like. A chain needs all sorts of metals, and a land needs all sorts of people.”
“And so?”
“The Night’s Watch needs all sorts too. Why else have rangers and stewards and builders? Lord Randyll couldn’t make Sam a warrior, and Ser Alliser won’t either. You can’t hammer tin into iron, no matter how hard you beat it, but that doesn’t mean tin is useless. Why shouldn’t Sam be a steward?
...
“He could help you. He can do sums, and he knows how to read and write. I know Chett can’t read, and Clydas has weak eyes. Sam read every book in his father’s library. He’d be good with the ravens too. Animals seem to like him. Ghost took to him straight off. There’s a lot he could do, besides fighting. The Night’s Watch needs every man. Why kill one, to no end? Make use of him instead.”