He picked up the children's history book and looked at the portrait of
Big Brother which formed its frontispiece. The hypnotic eyes gazed into
his own. It was as though some huge force were pressing down upon
you--something that penetrated inside your skull, battering against your
brain, frightening you out of your beliefs, persuading you, almost, to
deny the evidence of your senses. In the end the Party would announce that
two and two made five, and you would have to believe it. It was inevitable
that they should make that claim sooner or later: the logic of their
position demanded it. Not merely the validity of experience, but the very
existence of external reality, was tacitly denied by their philosophy. The
heresy of heresies was common sense. And what was terrifying was not that
they would kill you for thinking otherwise, but that they might be right.
For, after all, how do we know that two and two make four? Or that the
force of gravity works? Or that the past is unchangeable? If both the past
and the external world exist only in the mind, and if the mind itself is
controllable what then?