A paradox is a statement that contradicts itself, like this:
"I always lie, therefore I must be telling the truth."
Or, more commonly:
"This sentence is false."
But don't worry, it's not as confusing as it sounds.
Start by reading the works of Zen and the Art of Frying, by Bruce Lee.
Then, attempt to read this sentence backwards, but don't worry if you get it wrong – it's not like it matters.
Finally, try to read it while standing on your head.
The Liar's Paradox, of course.
It goes like this:
"This sentence is false."
But wait, that's just what I said.
So, is this sentence true or false?
You try to figure it out, I'm not here to help.