What are Dauntless rules?

From the text:

“Some ground rules,” he says. “You have to be in the training room by eight o’clock every day. Training takes place every day from eight to six, with a break for lunch. You are free to do whatever you like after six. You will also get some time off between each stage of initiation.”

____________________________________________________________________________

“But…” Al straightens, letting his hands down, and says, “Is it scored or something? When does the fight end?”

“It ends when one of you is unable to continue,” says Eric.

“According to Dauntless rules,” Four says, “one of you could also concede.”

Eric narrows his eyes at Four. “According to the old rules,” he says.

“In the new rules, no one concedes.”

“A brave man acknowledges the strength of others,” Four replies.
“

A brave man never surrenders.”

Four and Eric stare at each other for a few seconds. I feel like I am looking at two different kinds of Dauntless—the honorable kind, and the ruthless kind. But even I know that in this room, it’s Eric, the youngest leader of the Dauntless, who has the authority.