Imagine a Snakes and Ladders board. Two player-pieces on the board. They are talking.
One says, "what's it all about"?
The other says, "well, there are these squares, and there is this die. We roll the die, and we move forward based on what comes up -- it's all random."
"In fact, our state of knowledge has advanced to the point where we now know the exact number of squares: 100".
"Isn't it a bit odd that there are exactly 100 squares".
"Not at all. There has to be some number, and 100 is just as likely as 97 or 101 -- there's a 100% probability that the number would be 100!".
"But why", the other asks, "do we sometimes advance upwards, and, other times, slide downwards?
"Well, we used to believe that some mysterious force caused this. But, we've investigated and discovered previously unknown entities called ladders. When we land on a ladder, it has the effect of taking us up to the next level."
"What about down?"
"We've investigated that, too. We've discovered dark entities known as snakes. Snakes have the property of being slippery. When we land on a snake, we slide down."
"Is there any rhyme or reason to the position of the snakes and ladders?"
"No, they're all quite random. Doesn't make any sense at all, really. If any of this were designed, we could have done a much better job of it!".
"And what happens if and when one of us reaches the top square?"
"The first one of us to reach the top wins!".
And that, ladies in gentlemen, is a complete, full, and final explanation of the snakes and ladders game.
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