ELI5: Explain Like I'm 5

Four valued logic

Have you ever played a game where you had to choose between two options - like choosing between chocolate or vanilla ice cream? Well, what if there were more than just two options? What if you had to choose between chocolate, vanilla, strawberry, and raspberry ice cream?

In four valued logic, instead of just having two options like true or false, there are four options to choose from. These options are true, false, unknown, and undefined.

True means that something is definitely right or correct. False means that something is definitely wrong or incorrect. Unknown means that we don't have enough information to make a decision yet. And Undefined means that something can't be proven or doesn't make sense.

So, if we were using four valued logic to understand if it was raining outside, true would mean that it is definitely raining, false would mean that it is definitely not raining, unknown would mean that we aren't sure if it's raining or not, and undefined would mean that it doesn't make sense to talk about whether it's raining or not - like if we were trying to use four valued logic to determine if a unicorn was standing outside our window.

Overall, four valued logic helps us make decisions even when we don't have all the information we need, or when some things just can't be proven one way or the other.
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