<p>'As entertaining as it is engrossing' John Banville<br><br>'Enlightening, delightful' Arthur der Weduwen, author of<br>The Library<br>Why don't eleven and twelve end in ?teen? The rest of our counting system sits in neatly arithmetical sets of ten, so why do these two rulebreakers seem so at odds with the numbers that follow them?<br>Admittedly, that's probably a question that might never have occurred to you. But if you're even remotely inter...