Okay kiddo, imagine you're playing a game of hide and seek with your friends. One friend, let's call him Bob, says he's going to hide and you have to find him. But then another friend, let's call her Sally, tells you that Bob says he's invisible and you'll never be able to find him. This makes it very tricky to play the game because you don't know if Bob is actually hiding or just pretending to be invisible.
Now, let's talk about Epimenides. He was a man from a long time ago who lived on an island called Crete. There's a story about Epimenides that goes like this: he said "all Cretans are liars." This might not seem like a big deal, but it causes a problem because Epimenides himself was a Cretan. So if he's saying that Cretans are liars, does that mean he's lying too? It's like Bob pretending to be invisible – it confuses things and makes them hard to figure out.
This is called a paradox. A paradox is something that seems contradictory or doesn't make sense, but is actually true. So when Epimenides said that all Cretans are liars, it created a paradox because he himself was a Cretan. This makes it hard to know what to believe or how to make sense of what he said.
So, in summary, Epimenides was a guy from Crete who said something that created a paradox – a confusing situation where it's hard to know what's true or not. Just like Bob pretending to be invisible in our game of hide and seek.