The desire to economize time and mental effort in arithmetical computations, and to eliminate human liability to error is probably as old as the science of arithmetic itself.
“I moved around 13 different times before I was in fifth grade, not having money, not having a lot of friends.”
“When I had no shoes I was comfortable - I used to run barefoot. When I wore shoes it was difficult. To run in shoes was ok, but at the beginning of my career it was hard.”