Please entertain me while I retell a story:
A professor of mathematics is arrested by the secret police. They decide to get rid of him and inform the man that he will be executed at dawn some time during the next week, but he will not know the day until it happens.
So our mathematician sits in his dark cell and reasons to himself: "If by Saturday after dawn I am still alive, then they will surely have to kill me on Sunday because it would be the only remaining day. But then I would know it on Saturday, so for certain Sunday cannot be the day. Hence, if by Friday I am still alive, then they must kill me on Saturday. But I would know on Friday that Saturday is the day, so surely that cannot be the day either. I can eliminate Friday the same way, then Thursday, and every day. If the sentence is true, then they cannot kill me on any of these days. So it cannot be true."
They shot him on Thursday. He never saw it coming.
Okay, it's not a very funny joke. But what I do enjoy about the paradox is how it demonstrates that we can see the time and times and half a time, and still not know anything of the day nor the hour.
