“I don’t know what I’m looking for.”“What not?”“Because … because … I think it might be because if I knew I wouldn’t be able to look for them.”

“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 don't know what this great thing I'm meant to be doing is, and it looks to me as if I was supposed not to know. And I resent that, right? "The old me knew. The old me cared. Fine, so far so good. Except that the old me cared so much that he actually got inside his own brain--my own brain--and locked off the bits that knew and cared, because if I knew and cared I wouldn't be able to do it. [...] "But this former self of mine killed himself off, didn't he, by changing my brain? Okay, that was his choice. This new me has its own choices to make, and by a strange coincidence those choices involve not knowing and not caring about this big number, whatever it is. That's what he wanted, that's what he got. "Except this old self of mine tired to leave himself in control, leaving orders for me in the bit of my brain he locked off. Well, I don't want to know, and I don't want to hear them. That's my choice. I'm not going to be anybody's puppet, particularly not my own. [...] "The old me is dead! [...] Killed himself! The dead shouldn't hang about trying t0 interfere with the living.”

“Hey, er ..." said Zaphod, "what's your name?"The man looked at them doubtfully."I don't know. Why, do you think I should have one? It seems very odd togive a bundle of vague sensory perceptions a name.”

“When the girl sitting at the next table looked away from a moment, Dirk leaned over and took her coffee. He knew that he was perfectly safe doing this because she would simply not be able to believe that this had happened.”

“What was the self-sacrifice?"I jettisoned half of a much-loved and I think irreplaceable pair of shoes."Why was that self-sacrifice?"Because they were mine!" said Ford, crossly.I think we have different value systems."Well mine's better.”

“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.”