From Philip K. Dick's 1978 article "How to Build a Universe That Doesn't Fall Apart Two Days Later" (emphasis mine):
The basic tool for the manipulation of reality is the manipulation of words. If you can control the meaning of words, you can control the people who must use the words. George Orwell made this clear in his novel 1984. But another way to control the minds of people is to control their perceptions. If you can get them to see the world as you do, they will think as you do. Comprehension follows perception.
How do you get them to see the reality you see? After all, it is only one reality out of many. Images are a basic constituent: pictures. This is why the power of TV to influence young minds is so staggeringly vast. Words and pictures are synchronized. The possibility of total control of the viewer exists, especially the young viewer. TV viewing is a kind of sleep- learning. An EEG of a person watching TV shows that after about half an hour the brain decides that nothing is happening, and it goes into a hypnoidal twilight state, emitting alpha waves. This is because there is such little eye motion.
In addition, much of the information is graphic and therefore passes into the right hemisphere of the brain, rather than being processed by the left, where the conscious personality is located. Recent experiments indicate that much of what we see on the TV screen is received on a subliminal basis. We only imagine that we consciously see what is there.
The bulk of the messages elude our attention; literally, after a few hours of TV watching, we do not know what we have seen. Our memories are spurious, like our memories of dreams; the blanks are filled in retrospectively. And falsified. We have participated unknowingly in the creation of a spurious reality, and then we have obligingly fed it to ourselves. We have colluded in our own doom.
(via email from Anirudh)
When you're young, you look at television and think, There's a conspiracy. The networks have conspired to dumb us down. But when you get a little older, you realize that's not true. The networks are in business to give people exactly what they want. That's a far more depressing thought. Conspiracy is optimistic! You can shoot the bastards! We can have a revolution! But the networks are really in business to give people what they want. It's the truth.
-- Steve Jobs quoted in Wired (February 1996)