Be it noted: I am writing this on the first weekend of a five-weekend month. You are reading it on the second of those five weekends. If that’s awe-inspiring enough for you, or even if not, quiver in your boots and read on. I’ll return to weekends shortly.
Remember the September 1993 earthquake in Latur? Soon after that monumental tragedy, a seething pile of astrologers (OK, a couple) crawled from the woodwork to tell us about a sequence of disasters that had struck the country every nine years:
• 1948: Mahatma Gandhi assassinated
• 1957: Dr Ambedkar dead
• 1966: Air India crash in Switzerland
• 1975: Indira Gandhi declared the emergency
• 1984: Indira Gandhi assassinated (though why didn’t they pick the massacre of 3,000 afterwards? Or Bhopal?).
• 1993: Latur earthquake
Also read | Dilip D’Souza’s earlier columns
Uncanny, right? But they had a clincher. (Astrologers often do). Add up the digits in each of those years. You get 22, every time! The astrologers promptly tarred and feathered the number 22. India’s unlucky number, they said, and plenty of us quivered in our boots. (22-year-olds, especially so).
So what does 22 have to do with disasters in India?
Short answer: nothing. Long answer: absolutely nothing.
Here’s what those post-quake astrologers were silent about. Take any two numbers that differ by nine and add up their digits, you’ll get the same total; if not, add the digits of the resulting number, repeating if necessary, till you get a single digit total (2 + 2 = 4, in this case). This single digit is called the “digital root” of the number, and numbers that differ by nine have the same digital root.
Amazing? But it really isn’t. This property of the number nine is a trivial consequence of using the decimal system, where we count in 10s. If we had eight fingers and not 10, and thus followed the octal rather than decimal system, the same property would have held for seven and not nine. If we had 37 fingers—I’m truly glad I don’t—the same thing would have happened with 36.
But back to that strange breed, astrologers. Simply by picking years that differ by nine, they can make this portentous claim: that the digits add up to the same number. They’re sharp that way, astrologers.
“Got that”, you say, “but what’s this about a major disaster every nine years?” In fact, consider the next two entries in that sequence:
• 2002: Massacre in Gujarat
• 2011: Take your pick
Why, oh, why is India blighted at nine-year intervals?
Short answer: It isn’t. Long answer: It really isn’t.
What astrologers are really sharp at is finding real-world happenings to retrofit to their fantasy world of dire prediction. In this case, they know that any given year will have at least a few major disasters or deaths of major figures. Take a look. 1962? War with China. 2008? Terrorist attack in Bombay. 1999? Orissa cyclone. 1991? Rajiv Gandhi assassinated. Try it yourself.
So don’t get fooled by astrologer friends who trot out “evidence” to show that some number is a malevolent menace to India. But give them credit for recognizing and playing on something all of us like: patterns. Including the recent bunk about this being the first July in 823 years with five weekends. Never mind that July 2005 had five weekends, as will July 2016.
There’s something strangely comforting about discovering patterns in the daily randomness of events. Nine, 22— these are pegs to hold on to, thumbs to suck. If we suffer inexplicable calamities every now and then, we can tell ourselves there’s nothing to be done, because some cosmic eminence with a mysterious affinity for 22 has got it in for us.
Yet, the real marvel is that randomness itself produces patterns. Put another way, in any random sequence of anything, you’ll find patterns. If you tossed a coin 16 times, for example, what are the chances that at least one sequence of four heads or four tails in a row will show up? I’m guessing that you’re guessing “kind of low, pal!” So I’m also guessing that you’ll be astonished to learn that such a sequence is close to certain. And four heads or tails in a row is only one kind of pattern. In just those 16 tosses, any of us would find several patterns.
In any sequence of years, any of us would find several patterns. Including disasters, including five-weekend months.
So when astrologers start using patterns for solemn pontification, we should call their bluff. Because trivial mumbo-jumbo cannot trump reason and thinking.
Raymond Smullyan, legendary logician, was once asked if he believed in astrology. “I don’t”, he said, “and the reason I don’t is that I’m a Gemini.”
The year was 1975. Smullyan was 22. For the first time in 98,217 years, March followed February.
All right, it wasn’t 1975. He wasn’t 22.
Once a computer scientist, Dilip D’Souza now lives in Mumbai and writes for his dinners. A Matter of Numbers will explore the joy of mathematics, with occasional forays into other sciences. Comments are welcome at firstname.lastname@example.org