“If you insist on disavowing that which is ugly about what you do," said Magnus, still looking at Alec, "you will never learn from your mistakes.”

“In our modern world, we look unkindly on mistakes and imperfection. But this is far from the samurai ideal. Mistakes are part of the learning process and if you haven't made them then you are, indeed, dangerous because it means you have never learned anything. Mistakes, to a samurai, are the proof of your learning.”

“I'll never make that mistake again, reading the experts' opinions. Of course, you only live one life, and you make all your mistakes, and learn what not to do, and that's the end of you.”

“Alec said you do that," said Jace. "Deflect questions about yourself with jokes.”

“Alec looked merely irritated by this comment. "The only way you could raise enough money to hire Magnus by selling lemonade is if you put meth in it.”

“Magnus, we’re going down to the lake," he said. "Do you want to come?"
“Why?” Magnus inquired.
Alec shrugged, “Clary says it’s pretty,” he said. “I mean, I’ve seen it before, but there was a huge angel rising out of it, and that was distracting.”

“You are human, you will make mistakes, and it’s one of the most beautiful things about being human, but you must learn from your mistakes, otherwise your life will have a lot of unnecessary pain.”

“You must never feel badly about making mistakes… as long as you take the trouble to learn from them. For you often learn more by being wrong for the right reasons than you do by being right for the wrong reasons.”

“I done learned my mistake and learned to do what's right by it. You still trying to get something for nothing. Life don't owe you nothing. You owe it to yourself.
- Troy”

“Are you still mad because i broke your phone" Jace said. "Because you broke my wrist, so i'd said we're even"
"It was sprained," Alec said. "Not broken, sprained”