‘The Philosophers’ by Adam Ehrlich Sachs
From The New Yorker:
A philosopher had spent his lifetime pondering the nature of knowledge and was ready at last to write down his conclusions. He took out a sheet of white paper and a pen. But he noticed, upon lifting the pen, a slight tremor in his hand. Hours later he was diagnosed with a neuromuscular disorder that promptly began ravaging his body, though apparently, according to the doctor, not his mind.
He lost the use of his muscles one by one, first in his fingers, then in his toes, then in his arms, then in his legs. Soon he could only whisper weakly and flutter his right eyelid. Just before losing the power of speech entirely, he designed with his son’s help a system by which he could communicate, through twitches and blinks, the letters of the alphabet.
Then the philosopher fell silent.