[ WP ] Every person has the ability to go back and change the past exactly once . But if anything too significant is changed , everyone influenced directly by the change turns into the mental equivalent of a vegetable .

Survivor bias. 
 
 After the happening, there was much excitement and fear over mankind's new power. Pundits and preachers alike screamed the world was headed to hell within a week. 
 
 As it turned out, the very nature of changing the past made the activity quite self limiting. And Mankind caught on quick. Change too much and pay dearly. Change too little and no one noticed anyway. The wreckage of a change gone wrong lay everywhere. The monuments to a change gone right? Well, those were too tiny to see. 
 
 The only feedback was from the events they could see the effect of. When something went wrong. It had been years since there was a confirmed case of time travel. 
 
 Survivor bias. 
 
 The PSAs still ran though. On every station during every program. Samantha knew the risk. Everyone did. If anyone still took the chance, no one talked about it. There was some doubt if mankind still possessed the ability at all. 
 
 Ten years in this place. Ten years of the orderlies half smiles. Ten years of visits from the elementary school chorus, once at Easter, once at Christmas. 
 
 Samantha was sore. Someone had turned the heat down. Being cold always made her sore. She glanced over at the alarm clock. 1AM. The chairs in the senior center were too hard for her these days but her bed seemed a trip too far. 
 
 She returned her focus to the TV. The PSA stopped and the channel cut to infomercials. Samantha frowned. She closed her eyes, bit her lip, and stepped through time. 
 
 Things were much brighter. The garage door was opened directly on the sun. Paul was in the passenger seat, clutching his chest. He'd loose consciousness any minute now. 
 
 Samantha looked on her husband for the last time again. She chose to smile this go round. 
 
 She took Paul's hand from his chest and held it tight. Paul, too, managed a smile this time. 
 
 Samantha closed her eyes, turned the key, pressed the remote to close the garage door, and asked a small favor of the universe. 
 
 `` Please, let us be just small enough.''
