“If such a thing called happiness exists in this world, it should be something which resembles the limitless nothingness. Nihility is having nothing and having nothing to lose. If that isn't "happiness", then what is?”

“Hearts, you say? You Humans are always so quick to speak of such things. As though you carry your hearts in the very palms of your hands. But this eye of mine perceives all. There is nothing that it overlooks. If this eye cannot see a thing, then it does not exist. That is the assumption under which I have always fought. What is this "heart"? If I tear open that chest of yours, will I see it there? If I smash open that skull of yours, will I see it there?”

“In this world, perfection is an illusion. Reagrdless of all those who utter the contrary, this is the reality. Obviously mediocre fools will forever lust for perfection and seek it out. However, what meaning is there in perfection? None. Not a bit. ...After perfection there exists nothing higher. Not even room for creation which means there is no room for wisdom or talent either. Understand? To scientists like ourselves, perfection is despair. - Kurotsuchi Mayuri (Bleach 306)”

“Every thing in this world exist to wear you down”

“The perfect being, huh? There is no such thing as perfect in this world. That may sound cliché, but it’s the truth. The average person admires perfection and seeks to obtain it. But, what’s the point of achieving perfection? There is none. Nothing. Not a single thing. I loathe perfection! If something is perfect, then there is nothing left. There is no room for imagination. No place left for a person to gain additional knowledge or abilities. Do you know what that means? For scientists such as ourselves, perfection only brings despair. It is our job to create things more wonderful than anything before them, but never to obtain perfection. A scientist must be a person who finds ecstasy while suffering from that antimony. In short, the moment that foolishness left your mouth and reached my ears, you had already lost. Of course, that’s assuming you are a scientist”

“No, nothing can change my world--Ichigo Kurosaki, Black Moon Rising”

“Rukia, let me ask you something. From your experience where do you think your heart is?" "um well if I had to guess I think somewhere around here isn't that right?" "If you want to be literal about it. But in my opinion it's more a state of mind. I believe its right here, not inside our bodies at all. I think a heart is created between people when they meet for the first time, a bond that's brought to life between individuals. It's an emotional connection, when you think about something or care about someone, that's where your heart is born. If you were the only person that existed in this world, your heart would have no way of forming so it just wouldn't be anywhere. There's nothing to worry about Rukia. If you believe with all of your heart that you belong here, then this is where you'll stay. If your heart is here then that's all the reason in the world you need to be here. You must never doubt that. But listen Rukia, in the fights to come, there's something I must warn you about. Something you must promise me you will never ever do. I mean this. You must never die alone. Our souls are our bodies and when we die our bodies turn to dust and become the reishi that go on to form the soul society, but where do our hearts go? We entrust our hearts to our friends. If you entrust your heart to your friends it will continue to live on inside them. That's the most important thing you'll learn from my training. Don't you dare die alone Rukia.”