Measure.

Alan could tell distance, length, height, width, inseam, you name it, by a mere cursory glance at any person, object or animal. He would hold his thumb and forefinger at precisely one inch from each other and would go on to say: "This, this is how it all got started that day when I placed these two fingers on that Westcott ruler. I was but a child, but now, as I stand 37 & 3/8ths of an inch in front of you, I can finally say that I am the Master of Measure."
His friends advised him that he should become an interior designer or a surveyor, but instead, he preferred to observe the anoles on the trees and measure their tails from afar, along with tree's height, and the width of its leaves.
Time passed and Alan realized that he could not really make a living from watching and measuring the local flora & fauna. Seeing that measuring was his only skill, he decided to travel abroad in search of fame and fortune. Unfortunately, he chose France as his destination, and it proved his undoing. Confident of his abilities he took a job as a tailor's assistant in the town of Nimes. Alas, his stroke of luck was very short lived, as he found out on the first work-day. When asked for the length of a certain piece of very expensive corduroy, he swiftly answered: "But of course, it's 3 yards and 2/5ths", which produced only blank stares from the tailor and the customer. Alan was an expert measurer, no doubt, yet he could not measure using the metric system, and for all intents and purposes, he was speaking Sanskrit to the Frenchmen.
He tried to use his fingers..."See, this is one inch, this times 36 is one yard, it's all quite easy you know".
All his efforts were in vain.
The tailor was a kind and understanding man, and tried to teach Alan the metric system, but it seemed that the very same gift that Alan had for inches, feet & yards made it impossible for him to learn about millimeters or centimeters. Many months passed, and the tailor-not being well off himself-was inevitably forced to dismiss Alan, who then wandered eastward, all the while muttering to himself: "this is one inch, it's easy...this is one inch, it's easy", over and over again, until it reached the point that his hands became atrophied in the "one inch" position. He travelled as far as Moldova, where he was eventually taken in by a group of itinerant Roma who showcased him until old age as "The Crazy Gadje with the Claw Hands".

FIN