system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What is fuzzy logic and how is it that it's found in missiles and rice cookers?
gpt
Traditional logic only knows two states: True or False. Is the rice cooker hot enough? If yes, turn off the heating element, and if not, turn it on.

Fuzzy logic can also express to what extent a statement is true on a sliding scale. Is the rice cooker hot enough? No, but it's close, so turn down the heating element a bit.

In a lot of control systems that extra information can be beneficial because it allows the control logic to make better decisions. In the rice cooker for example the heating element has a certain amount of thermal mass, and even if you turn it off, it will remain hot for a few moments and continue to heat the rice even without power going to it.

That means you will overshoot the desired temperature by a bit if you keep it powered at 100% until you reach the target temperature. And if you keep it at 0% until the temperature falls below the target, the heating element will need a few moments to heat up when you do turn it on, so there's going to be undershoot as well. So instead of maintaining a constant 60°C to keep the rice warm, the actual temperature may oscillate between 57°C and 63°C. If the controller is smart enough to reduce the output of the heating element when it approaches the target temperature, there's not going to be as much overshoot.