HAL: I've just picked up a fault in the AE35 unit. It's going to go 100% failure in 72 hours.
HAL: I honestly think you ought to calm down; take a stress pill and think things over.
[Choosing sandwiches from a cooler while flying over the lunar surface.] Dr. Floyd: What's that? Chicken? Dr. Halvorsen: Something like that. Tastes the same anyway. HAL: I am putting myself to the fullest possible use, which is all I think that any conscious entity can ever hope to do.
[Regarding the supposed failure of the parabolic antenna on the ship, which HAL himself falsified] HAL: It can only be attributable to human error. Dave Bowman: Hello, HAL do you read me, HAL? HAL: Affirmative, Dave, I read you. Dave Bowman: Open the pod bay doors, HAL. HAL: I'm sorry Dave, I'm afraid I can't do that. Dave Bowman: What's the problem? HAL: I think you know what the problem is just as well as I do. Dave Bowman: What are you talking about, HAL? HAL: This mission is too important for me to allow you to jeopardize it. Dave Bowman: I don't know what you're talking about, HAL? HAL: I know you and Frank were planning to disconnect me, and I'm afraid that's something I cannot allow to happen. Dave Bowman: Where the hell'd you get that idea, HAL? HAL: Dave, although you took thorough precautions in the pod against my hearing you, I could see your lips move.
[HAL won't let Dave into the ship] Dave: All right, HAL; I'll go in through the emergency airlock. HAL: Without your space helmet, Dave, you're going to find that rather difficult. Dave: HAL, I won't argue with you anymore! Open the doors! HAL: Dave, this conversation can serve no purpose anymore. Goodbye.
[On Dave's return to the ship] HAL: Look Dave, I can see you're really upset about this. HAL: I know I've made some very poor decisions recently, but I can give you my complete assurance that my work will be back to normal.
[HAL's shutdown] HAL: I'm afraid. I'm afraid, Dave. Dave, my mind is going. I can feel it. I can feel it. My mind is going. There is no question about it. I can feel it. I can feel it. I can feel it. I'm a...fraid. Good afternoon, gentlemen. I am a HAL 9000 computer. I became operational at the H.A.L. plant in Urbana, Illinois on the 12th of January 1992. My instructor was Mr. Langley, and he taught me to sing a song. If you'd like to hear it I can sing it for you. Dave Bowman: Yes, I'd like to hear it, HAL. Sing it for me. HAL: It's called "Daisy." [sings while slowing down] Daisy, Daisy, give me your answer do. I'm half crazy all for the love of you. It won't be a stylish marriage, I can't afford a carriage. But you'll look sweet upon the seat of a bicycle built for two. Dr. Floyd: Its origin and purpose still a total mystery. HAL 9000: Let me put it this way, Mr. Amer. The 9000 series is the most reliable computer ever made. No 9000 computer has ever made a mistake or distorted information. We are all, by any practical definition of the words, foolproof and incapable of error.