George Orwell's prescient work 1984 foresees tyranny's need for propaganda that renders listeners incapable of critical thought, to the point that they cannot process what is in front of their eyes.
Fine illustration was given in the early minutes of the movie 1984, as we learn the daily routine of Winston (the protagonist). To a loudspeaker incessantly broadcasting statistics demonstrating Big Brother's progress in all areas of life, we witness their physical impoverishment (a colleague asking for a razor blade learns that Winston has been using the same blade for six weeks), as well as (through another colleague) Big Brother's assault on language as a way to control thought. We also witness the inability of the brainwashed to process the world they inhabit: the loudspeaker's lies about Big Brother's successes cheers up Parson while he works his way through a bowl of mush and meat-substitute. He is so indoctrinated he cannot process the reality in which he is sitting or even the food he is tasting.
Here is another situation that resembles this scene from 1984. Yesterday in the United States Senate, a British actuary presented the following information from the UK (which has excellent public health surveillance): getting vaccinated makes one somewhere between 26% and 145% more likely to die.
Yet I know plenty of educated, normally sensible people, who cheerfully continue their defense of Big Brother's handling of Covid-19. They espouse their willingness to continue subjecting themselves to shots with all the alacrity of 1984's Parson, reciting statistics about Big Brother's successes while shoveling down gruel and meat-substitute with gusto.