Potter fans crack the code

By Burkard Polster and Marty Ross

The Age, 3 November 2008

A popular method of concealing secret messages is to hide them in something inconspicuous. One way is to make the letters of the message appear equally spaced throughout a larger text. For example, the word “FeAsT” conveniently contains the warning message “FAT”, with the letters of the message spaced two letters apart.

The infamous Cardinal Richelieu and Sir Francis Bacon are two of the historical figures who used similar techniques to conceal messages. And there are presumably many other cunning examples that we do not know about. There is now a minor industry looking for such messages in famous texts.

In the 1990s a group of researchers struck gold. They, and those who followed, found many equally spaced messages hidden in the Torah. The amazing messages from God (we presume) included warnings about the Holocaust, the assassination of a Middle East leader, September 11, and the Bali Bombings. The Bible Code, a collection of many of these messages was an instant bestseller when it appeared in 1997. Unfortunately all but one of these warnings were discovered after the fact (guess the exception).

Brendan McKay, a Statistician at Australian National University, has been a key figure in the debunking of the Bible Code. Brendan and his colleagues proved that such “messages” can statistically be expected in any long text. A very funny pair of examples are: a message in the Book of Genesis claiming “There are codes in Moby Dick”; and a message in Moby Dick asserting “No Code in the Torah”.

To give you a rough idea of the mathematics involved, an English Bible has about 3 500 000 letters. Suppose we then want to hunt for the 5-letter word “maths”. This gives about 700 000 possible spacings. Taking account of where the string can begin, this gives about 10¹² equally spaced 5-letter strings in the Bible. But there are about 107 different five-letter strings that can be made from our alphabet. This means “maths” should appear as a sequence in the Bible about 100 000 times.

So, the Bible Code didn’t pan out. But perhaps messages are coded in the Bible by a different scheme. Recently, we checked the Harry Potter books for such messages and discovered something truly amazing in The Half-Blood Prince.

On the last page we read “Harry looked at him, startled; the idea that anything as …”. Focus on the underlined words. “Harry” has five letters, and the fifth word after Harry is the second underlined word “the”. This word has three letters and three words later is the next underlined word, “anything”. If we keep on going, we finally end on the word “enjoy”. At this point there are only four more words and we have to stop.

What if, instead of “Harry”, we had started on the word “Voldemort” on the same page? We still end up at “enjoy”. This may be a coincidence. However, it turns out that no matter where you begin in the book (except on the last few lines), you always arrive at the same word, the magical message to “enjoy”.

Even stranger, we found that each Harry Potter book contains such a magical word. Has J.K. Rowling been leaving secret messages for her especially dedicated readers? Or can the mathematical spoilsports amongst you come up with an easy explanation of this phenomenon? Email us with your queries and your comments.