The most important question to ask yourself when considering building a digital version of a 75-year-old hydraulic computer is also the most obvious: why?
Thankfully, in the case of Bill Phillips’s wonderfully inventive contraption, that question is easy to answer. First, there’s the historical value of the machine itself. It is a triumph of analogue technology, constructed at a time when electronic computing was in its infancy. With only 14 machines ever built, and just three of them operational today, it’s an obvious candidate for digital preservation.
Second, the Phillips machine has enduring value as a teaching aid. In 2017, Kristin Forbes, then an external member of the Bank of England’s Monetary Policy Committee, said she regularly referenced the Moniac in her classes at MIT, praising it as “an entertaining way to teach basic macroeconomic relationships”.