LAWRIE McFARLANE

Astrology takes advantage of timeless traits of human nature

Gov. Gen. Julie Payette has been clobbered for rubbishing believers in horoscopes, astrology and such like. In a speech to the Canadian Science Policy Convention in Ottawa, these are, she asserted, pure fakery.

In passing, you have to wonder why her advisers let the GG make such tone-deaf remarks. Practically the only requirement of this antiquated sinecure is to stay away from controversy. Instead, she stepped in it with both feet.

Of course, it’s always possible she doesn’t listen to her aides. Perhaps, as a former astronaut, Payette believed that having “slipped the surly bonds of Earth,” she knows more about the stars than astrologers.

And in one respect, of course, Payette is right. Any reasonable person knows astrology, fortune-telling and horoscopes are nonsense. Taken at face value, the science they lay claim to does not exist. (Though that didn’t stop Ronald Reagan’s wife Nancy from recruiting a self-proclaimed psychic, Joan Quigley, to prevent her husband’s assassination. I suppose Quigley took comfort from the fact that although Reagan was shot on her watch, he didn’t die.)

But interestingly, beyond the quackery there is, in fact, some science going on here. One of the principles that fortune-tellers rely on is what mathematicians call the law of truly large numbers.

In essence, spread your net wide enough, and just about anything is possible. Here are a couple of examples.

On Sept. 6, 2009, the Bulgarian lottery selected six winning numbers. Four days later, the same six numbers were chosen again. The odds of that happening are one in 13,983,816.

However, there are many lotteries in the world. Assuming we have at least 4,000, the odds that one of them will pick the same numbers twice in close succession are more than 50 per cent. Bulk up the sample size, and the wildly improbable becomes a betterthan-even bet.

Or suppose you are in a room with 22 other people. What are the chances that you will have the same birthday as any specific one of them? Answer, less than one per cent.

However, the chance that any random pair will have the same birthday is 50 per cent. That’s because in a group of 23, there are 253 possible pairs, and that dramatically improves the odds of getting a hit.

It’s this principle that fortunetellers rely on. Make enough prophesies, and some of them are bound to come true. The American astrologer Jeane Dixon became famous for predicting that president John Kennedy would be shot. People forget the thousands of times she was wrong.

A second principle that astrologers depend on is the Forer Effect. It works like this. Most human beings have a tendency to believe descriptions of their personality that are either complimentary to them or phrased in one-size-fits-all terms.

In a famous 1948 experiment, Prof. Bertram Forer gave each of his 39 psychology students a purportedly individualized précis of their personalities. These contained such broad statements as: “You pride yourself as an independent thinker” and “At times you are extroverted, affable, sociable.”

The students graded the sketches at 4.2 on a scale of 0 to 5, meaning they believed them to be accurate. In fact, each student had been given the same précis.

This is exactly the scam that astrologers are engaged in. Tell people what they want to hear, and they’re hooked. This isn’t so much fake science as clever psychology.

Payette missed the point. If some folks need to believe the universe contains more than science has revealed, scolding them won’t work.

We’re not talking about physics or math here, we’re talking about human nature. And history suggests it hasn’t changed much since the seers of ancient Greece held sway.