Mechanical Numeracy: Thinking With the Soroban Abacus in Modern Japan

The soroban is a traditional arithmetic tool whose life in modern Japan reflected an inherently material dimension of computational numeracy. Using a system of commands to carry out operations, the soroban was both doubted and enthusiastically embraced by educators as a way of teaching basic mathematics, sparking conversations of what it really meant to understand arithmetic. Despite the introduction of Western-style pen and paper arithmetic, it persisted as the standard tool of computing in households, businesses, and bureaucracy, driving the Taylorist training of human calculators who could apply its commands with corporal discipline and the design of mechanical calculators that simplified its procedures. Even when educators held an “intuitive” ideal of mental calculation that moved students away from calculating with physical tools, the soroban persevered as a virtual interface that calculators accessed in their minds.