"even in the darkest of suffering a man can sleep, but for the man who inflicts the suffering his mind can not rest, ever."
"The Philosophers' Stone: those who possess it, no longer bound by the laws of Equivalent Exchange in Alchemy, may gain without sacrifice, create without equal exchange. We searched for it, and we found it."
Humankind cannot gain anything without first giving something in return. To obtain, something of equal value must be lost. That is Alchemy's First Law of Equivalent Exchange. In those days, we really believed that to be the world's one, and only, truth. But the world isn't perfect, and the law is incomplete. Equivalent Exchange does not encompass everything that goes on here, but I still chose to believe in its principle: that all things do come at a price, that there's an end and a way, that the pain we work through did have a reward, and that anyone who's determined and perseveres will get something of value in return, even if it's not what they're expecting. I don't think of Equivalent Exchange as a law of the world any more. I think of it as a promise between my brother and me. A promise that someday we'll see each other again."