Humble Pi: When Math Goes Wrong in the Real World

by Matt Parker

I find that a lot of nostalgia about how things were manufactured better in the past comes down to survivor bias. I see people online sharing pictures of old kitchen equipment that is still working: waffle irons from the 1920s, mixers from the 1940s, and coffee machines from the 1980s. And there is some truth to the statement that older appliances last longer. I spoke to a manufacturing engineer in the US who said that, with 3D-design software, parts can be designed with much smaller tolerances now, whereas previous generations of engineers were not sure where the line was and so had to over-engineer parts to make sure they would work. But there is also the survivor bias, the fact that all the kitchen mixers that broke over the years have long been thrown out.