system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: I know many rice cookers use fuzzy logic (or fuzzy math?) So it cooks the rice the right amount of time. How does this work?
gpt
The basic ones are a bit simpler than “fuzzy” logic.

Water can only stay liquid up to 100 degrees C.

While there is liquid water in the cooker it’ll have a max temperature of 100C. Any excess heat put in gets used to turn the water to steam.

When all the water is absorbed or evaporated the temperature can climb above 100C

The cooker has a temperature sensitive strip on it that triggers just over 100C. This could be fancy circuits or it could be a bi-metallic strip with the right thermal properties. 

When all the liquid water is gone and the rice temperature goes above 100C the sensor trips and turns the cooker off.