“You cannot see what I see because you see what you see. You cannot know what I know because you know what you know. What I see and what I know cannot be added to what you see and what you know because they are not of the same kind. Neither can it replace what you see and what you know, because that would be to replace you yourself.""Hang on, can I write this down?" said Arthur, excitedly fumbling in his pocket for a pencil.”

“I'm a scientist and I know what constitutes proof. But the reason I call myself by my childhood name is to remind myself that a scientist must also be absolutely like a child. If he sees a thing, he must say that he sees it, whether it was what he thought he was going to see or not. See first, think later, then test. But always see first. Otherwise you will only see what you were expecting. Most scientists forget that.”

“I can see it, hear it, feel it, taste it - but I can never be on the inside of it with you. I cannot even be sure whether I really know what it is like. Is it 'like' my own? Or incomparable? Just as I can never know if what you see at any given moment is exactly the same as what I see. We look at a colour. We both call it red. But it is only because we have been taught to call it by that name. There is no guarantee - not ever - that we see it in the same way, that your red is my red.”

“He felt a spasm of excitement because he knew instinctively who it was, or at least knew who it was he wanted it to be, and once you know what it is you want to be true, instinct is a very useful device for enabling you to know that it is.”

“What you see is what you see, but that is never everything. Sarajavo is Sarajevo whatever you see or don't see. America is America. The past and future exist without you. And what you don't know about me is still my life. What I don't know about you is still your life. Nothing at all depends on you seeing it or not seeing it. I mean, who are you? You don't have to see or know everything.”

“Ok," he said, "I don't like to disturb you at what I know must be a difficult and distressing time for you, but I need to know first of all if you actually realize that this is a difficult and distressing time for you.”

“But the reason I call myself by my childhood name is to remind myself that a scientist must also be absolutely like a child. If he sees a thing, he must say that he sees it, whether it was what he thought he was going to see or not. See first, think later, then test. But always see first. Otherwise you will only see what you were expecting.”