The old Book of Riddles has 6329 pages Page 1 says page is lying 2 are And so on until Only one the book tells truth?

The last page is the one that tells the truth. If you read the rest of the pages:

- Page 1 says: "Page 2 is lying"

- Page 2 says: "Page 3 is lying"

- Page 3 says: "Page 4 is lying"

... and so on...

You get to the last page and it says the page before it is lying. But the page before it is the second to last page, so it must actually be telling the truth!