Here I am saying that mutants are dangerous to us ordinaries, a view which John W. Campbell, Jr. deplored. We were supposed to view them as our leade… - Philip K. Dick

"Let me sleep," he said, and shut the door; it clicked in her face and she felt animal terror - this was what she feared most in life: the clicking shut of a man's door in her face.
Instantly, she raised her hand to knock, discovered the rock... she banged on the door with the rock, but not loudly, just enough to let him know how desperate she was to get back in, but not enough to bother him if he didn't want to answer.
He didn't. No sound, no movement of the door. Nothing but the void.
"Tony?" she gasped, pressing her ear to the door. Silence. "Okay," she said numbly; clutching her rock she walked unsteadily across the porch toward her own living quarters.
The rock vanished. Her hand felt nothing.
"Damn," she said, not knowing how to react. Where had it gone? Into air. But then it must have been an illusion, she realized. He put me in a hypnotic state and made me believe. I should have known it wasn't really true.
A million stars burst into wheels of light, blistering, cold light, that drenched her. It came from behind and she felt the great weight of it crash into her. "Tony," she said, and fell into the waiting void. She thought nothing; she felt nothing. She saw only, saw the void as it absorbed her, waiting below and beneath her as she plummeted down the many miles.
On her hands and knees she died. Alone on the porch. Still clutching for what did not exist.

'A rolling stone gathers no moss.' Try as I might I could not remember the meaning. At last I hazarded, 'Well, it means a person who's always active and never pauses to reflect — ' No, that didn't sound right. I tried again. 'That means a man who is always active and keeps growing in mental and moral stature won't grow stale.' He was looking at me more intently, so I added by way of clarification, 'I mean, a man who's active and doesn't let grass grow under his feet, he'll get ahead in life.' Doctor Nisea said, 'I see.' And I knew that I had revealed, for the purposes of legal diagnosis, a schizophrenic thinking disorder. 'What does it mean?' I asked. 'Did I get it backward?' 'Yes, I'm afraid so. The generally-accepted meaning of the proverb is the opposite of what you've given; it is generally taken to mean that a person who — ' 'You don't have to tell me,' I broke in. 'I remember — I really knew it. A person who's unstable will never acquire anything of value.'

Human has always striven to retain the past, to keep it convincing; there's nothing wicked in that. Without it we have no continuity; we have only the moment. And, deprived of the past, the moment - the present - has little meaning, if any.