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Literature Study Guides2001 A Space OdysseyPart 4 Chapters 23 24 Summary

2001: A Space Odyssey | Study Guide

Arthur C. Clarke

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2001: A Space Odyssey | Part 4, Chapters 23–24 : Abyss | Summary



Chapter 23: Diagnosis

Back inside the two men test the old AE-35 unit, finding it to be working fine. They speculate about what could have gone wrong: Did Hal make a mistake, or is their testing device also faulty? Then they receive a message from Earth suggesting that Hal might have made a mistake. Mission Control has also detected a few small irregularities in Hal's performance over the past couple of days. They may need to disconnect Hal for a short time so diagnostics can be run.

Chapter 24: Broken Circuit

Within a few days Hal reports that the new AE-35 unit is malfunctioning. When asked about the cause of the problem, however, Hal doesn't have any ideas. He thinks it might be that the entire system is faulty, not just the unit. Bowman presses Hal, asking "Is something bothering you—something that might account for this problem?" Hal replies with, "I don't want to insist on it, Dave, but I am incapable of making an error."

Mission Control contacts Discovery with the conclusion that they need to fix Hal's programming. But before they can disconnect Hal and do this, Hal reports that communications with Earth have been lost because the AE-35 unit has failed. Poole and Bowman apologize to Hal for thinking he was mistaken before, since clearly the unit was faulty.


The suspense continues to grow as the possibility Hal is making errors becomes more and more likely. Mission Control sends the disconcerting information that Hal is likely making mistakes, but there is "no cause for alarm." Poole reports that Mission Control said this twice, in fact, but he notes that instead of being reassuring, the repetition "rather spoiled the effect." The fact that the computer tasked with keeping them alive and making sure they complete the mission is malfunctioning is a worry.

But even more of a worry is the fact that Hal's responses to the situation become hesitant, defensive, and argumentative. Though Hal can certainly hear Bowman, Poole, and Mission Control discussing him, he makes no comment. Over the next few weeks, he prefaces his remarks with a "brief electronic throat-clearing." He hesitates for an unusually long time when asked "what's causing the fault" in the AE-35 unit, and again when asked if there's something bothering him.

Bowman is clearly disconcerted by Hal's behavior, thinking that pushing further in the argument with Hal is not "safe" and wishing Hal could just forget the whole conversation. Hal's behavior is so suspicious that his relief that Bowman and Poole's confidence in him is restored when the AE-35 unit does fail does not seem like a positive development. It seems, in fact, to be a deliberate ploy on Hal's part to regain their trust. The increasingly deceptive behavior shown by Hal, and the way he must continually cover one lie with another follows a familiar, and very human pattern, raising the question of whether deception could be a defining human characteristic.

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