The Deus Ex Machina of Dr. Bowman

Some have argued that Hal goes insane because he has ordered to deceive the crew. And this introduces some kind of conflict into its programming or something like that. There's a debate over what exactly is the behind Hal's actions in the film. But I find the malfunctioning totally believable and all the more sinister for it, you know? If it can become inhuman and murderous even without having to sort of develop its own intelligence, if it can still be operating as a machine,. but one that suddenly turns on its maker, then that is really sinister and terrifying.