# Where Inductive Logic Cannot Be Applied

There are a lot of interview questions that involve inductive logic. The following is a good example:

Let's say there are 5 blue dragons on the island. The dragons are smart in a way that whenever they are given a statement, they can deduce the statement to its fullest. They die 24 hours after they know their own color, so they keep their mouths shut about it. However, one day, someone tells them 'hey. at least one of you is red.' Five days later, all dragons died.

This seems a bit counter-intuitive since the dragons already know that at least one of the dragons have the red color, so why would they die if someone tells them what they already know, but if we think about it from the beginning, it makes sense.

N=1 one dragon. after someone tells them 'hey. at least one of you is red,' the dragon dies next day.

N=2 two dragons. Let's call them dragon I, dragon II. Both dragons swill two days after someone tells them 'hey. at least one of you is red' because of the following reason:

If dragon I is not red, then we could reduce the problem to N=1 case right away, and the dragon II would've died next day, but if the dragon I saw dragon II alive next day, that means dragon I must also have red color, so they both die next day.

Following similar line of inductive logical reasoning, we can see that for N=5, all five dragons will die 5 days after they heard that 'at least one of you is red.'

Of course, When there's a color-blind dragon or a super-dumb dragon who cannot deduce anything from any statement or observation, every dragon will survive.

Now, however, I saw the following case where inductive reasoning cannot apply.

A good example is this: