What does "Would you kindly" mean in BioShock?

This page spoils the central twist of BioShock. Stop here if you have not finished it.

"Would you kindly" is a trigger phrase. Jack, the man you play, was conditioned from childhood to obey, instantly and completely, any instruction wrapped in those three words. The kindly voice guiding you by radio from the game's first minutes, the man who calls himself Atlas, knows it, and he has been steering you with it for the entire game: would you kindly pick up the radio, would you kindly find the family, would you kindly lower your weapon.

The reveal waits in Andrew Ryan's office, where the phrase is papered across the wall behind him, order after order, until the pattern becomes undeniable. Ryan then delivers the game's thesis in one line: "A man chooses, a slave obeys."

The trick is aimed at the player, not just the character. You obeyed Atlas for the same reason Jack did: the game asked, and following objectives is what players do. The phrase makes that habit the story.