referencing to the so-called mathematical problems proposed by the great german mathematician david hillberg and i had never heard of the guy. [laughter] >> this theory why if i said was true, that would put me in a very favorable light. it means i have nothing to do with the title. i mean, i can tell you exactly how the number came up. but then i worry you might be able to get -- you might disappointed by the story. well, 23 actually is a random number. how it came about -- you know, and one day -- i still remember exactly where it happened, you know, there's a station called paddington station in london, the paddington bear, and agatha christie paddington square and i did a poll with my literary agent this irish guy named ivan mulcahey and we looked at each other and we said 20. that's a bit boring, huh? so we started playing with the numbers and i said, look, i could probably write, i don't know, 30 things, 32 things or whatever. but that will make the book too big and he said why don't you start at 25 and we thought 25 is a bit obvious. i told him i don't like even numbers. 21, well, two