Discworld author and fantasy extraordinaire Sir Terry Pratchett passed away from a chest infection at age 66 this week. He had been diagnosed eight years ago with posterior cortical atrophy.
The condition didn't stop him from writing or interacting with fans, and many are already feeling his loss.
"The world has lost one of its brightest, sharpest minds," said publisher Larry Finlay, per BBC News.
Posterior cortical atrophy is a rare form of dementia that entails the progressive loss and dysfunction of cells. Dementia is a term for mental decline that is serious enough to affect daily life. Alzheimer's disease is the most common type of dementia.
Often seen wearing a trademark black hat, Pratchett left an indelible mark on the literary world and those looking to momentarily escape into an imaginative universe only he could have created.
That remained the case after his diagnosis. Pratchett had no interest in receding from public view because of the disease — instead becoming a face of survival.
"Over the last few years, it was his writing that sustained him," Finlay added. "His legacy will endure for decades to come."
And it won't be limited to his books alone. Pratchett was also a quite vocal when it came to raising awareness about Alzheimer's disease.
"Shouting from the rooftops about the absurdity of how little funding dementia research receives, and fighting for good quality dementia care, he was and will remain the truest of champions for people with the condition," said Alzheimer's Society Chief Executive Jeremy Hughes, per The Telegraph. "During the many times Terry supported Alzheimer's Society, publicly and privately, I was struck by his passion, resilience and courage to fight and kill the demon of dementia.
"When thanked for his work, he'd simply smile and shake his head modestly, insisting it was nothing. Never dwelling on his own dementia, he used his voice to shout out for others when they could not."
Thanks in large part to his first Discworld book in 1983, Pratchett went from working as a reporter (and later as a press officer for the Central Electricity Generating Board) to selling millions of copies from his series around the world. Even upon losing the ability to touch type in 2012, he kept writing with the use of voice recognition.
Knighted in 2009, Pratchett remained modest about his achievements, insisting at the time that his fame and fortune had a lot to do with luck.
In retrospect, it was almost certainly those who read and knew him who were the lucky ones.