He creates the Philosopher’s Stone and lives for over 600 years (PS17).
The year is based on the fact that, in 1991, Nicolas Flamel was said to have "celebrated his six hundred and sixty-fifth birthday last year."
This seems to agree with the historical Nicolas Flamel's birthdate, which is supposed to be circa 1330 (source: Wikipedia). -BB
If Flamel's age is given as being "665 last year" in an old book, doesn't that mean that he is really much older than that now? Assuming the book was a hundred years old, Flamel would be 766 now, not 666, right?
Assuming that the Nicolas Flamel of the Harry Potter universe is in any way similar to the Flamel of the real world, there is no conceivable way to rectify the dates of his birth and the age given in the old book Hermione discovers. However, there is a perfectly reasonable explanation for this discrepency. It is clear that the pictures in books are not the only things that move and change. The text must update itself as well, so as the years go by the age given by the book would change accordingly.
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