Someday they won't let you, so now you must agree
The times they are a-telling,
and the changing isn't free
You've read it in the tea leaves, and the tracks are on TV
Beware the savage jaw
Of 1984
They'll split your pretty cranium, and fill it full of air
And tell that you're eighty, but brother, you won't care
You'll be shooting up on anything, tomorrow's neverthere
Beware the savage jaw
Of 1984
Come see, come see, remember me?
We played out an all night movie role
You said it would last, but I guess we enrolled
In 1984 (who could ask for more)
1984 (who could ask for mor-or-or-or-ore)
(Mor-or-or-or-ore)
I'm looking for a vehicle, I'm looking for a ride
I'm looking for a party, I'm looking for a side
I'm looking for the treason that I knew in '65
Beware the savage jaw
Of 1984
This song by David Bowie explains the brainwashing of people, but metaphorically. He mentions "I'm looking for a party, I'm looking for a side" much like Winston, he didn't want to side with Big Brother's party. He searched for Goldstein's party and decided to choose that side of the party.
"They'll split your cranium and fill it with air" isn't favorite line. He is expressing how they will fill your head with useless things while brainwashing the things that they do not want you to know.