Horoscopes: A sign of the times

Are you going to meet a tall, dark, handsome stranger? Are you going to see change at home and at work? Are you going to have a visit from Lady Luck? Or are you just reading too many horoscopes?

January passes and, with it, reams of astrologers' predictions for the year ahead: love stars, money, health, destiny, friendship, style – even hair advice influenced by the constellations (the treats loveyourhair.com has in store include skillful use of layers to help Geminis hair swing almost as much as their moods).

But why, in an age when we are unlikely to dance to encourage weather change and wouldn't dream of throwing our neighbour in a river to see if she's a witch, do we read our star signs? Does anyone really find it credible that everyone sharing the same twelfth of the zodiac is imbued with the same characteristics?

If you're reading this and feeling smug, thinking that you play no part in the silliness of horoscopes, you're either in the minority or deceiving yourself: some 75 per cent of the population read horoscopes in magazines and newspapers, while a quarter go so far as to believe them.

Last week, despite a swift and strong denial by astrologers, news the Earth's "wobble" has shifted zodiac signs raced across the web like a shooting star. Minneapolis astronomer Parke Kunkle created an identity crisis as people struggled with the notion they'd slipped a star sign; modest Virgos, intuitive Cancers and passionate Scorpios were all left wondering about their true character as he confirmed a shift in the Earth's relationship to the sun over the past 2,000 years. Those born in December had even more to contend with: they'd become Serpent Handlers, in the 13th sign of Ophiuchus. One email Kunkle received demanded: "Give me my sign back."

Dr Chris French, professor of psychology at Goldsmiths University, who specialises in belief in the paranormal, is entirely sceptical about horoscopes – though he'll flick to his star sign in newspapers. "I do it for the same reason that half the population do: for entertainment," he explains. "Almost 25 per cent of people believe in astrology and a smaller percentage take it seriously enough to go for one-to-one readings."

Those figures have stayed consistent for 80 years, since horoscopes were first printed in newspapers, starting with the Sunday Express printing a birth horoscope for Princess Margaret Rose on 24 August 1930. French says: "Historically, people turn to astrology at times of social upheaval." He suggests it often appeals to people in, "careers where there is an inherent degree of uncertainty: sports people, actors, and, notoriously, gamblers".

Robert Downey Jnr and Britney Spears are believers, while Nancy Reagan would seek to influence the President's actions on astrologically auspicious days. In comparison, Cherie Blair's belief in crystals seems inconsequential. French also believes there's no correlation between education and belief in astrology, and classes it as a "New Age approach, maybe an alternative to organised religion".

But horoscopes are the victory of hope over reason: neither a star sign in a newspaper or a personal astrological reading has any truth. French says: "If you look at hundreds of empirical tests of astrology, they're very, very bad news for astrologers." This doesn't stop people persisting in believing their stars, nor from astrologers being adamant in their calling. For while horoscopes can't tell your fortune, they generate one.

Jonathan Cainer writes horoscopes for the Daily Mail and has a reputation for being the best-rewarded writer on Fleet Street, in no small part because of the success of his phone lines. At least 12 million people read his horoscopes, and his worldwide businesses turn over £2m annually and employ 30 staff. He defends astrology as: "a belief system with very rigid dogma. Saturn means restriction and Jupiter expansion. It's scientific in as much as we have to have accurate planetary positions. But it's a form of divination; a glorious blending of occult and science."

Dr French argues astrology is also about reassurance: "Take someone in an unhappy relationship: they know they should leave – but hearing they've got a difficult few months but will come through gives them courage." Not only are people inclined to believe what they hear, predictions involve clever sleights of tongue. Astrologers use tricks favoured by con-artists, creating the illusion of being specific while leaving room for reinterpretation. The Barnum effect comes into play, as astrologers rely on statements that seem specific but are universally relevant, such as: "On the surface you seem quite together, but deep down you have some insecurities".

French says: "I'm not saying most astrologers are deliberate con-artists, but they are subconsciously tapping into the techniques that make many successful."

Professor Richard Dawkins goes further in his dismissal, having said that: "Astrology may be slightly damaging, but mostly it is just sad. So sad that people are ignorant of the true glories of the stars and of the stupendous distances and times that separate them, while they bother with the frivolous inventions of charlatans." But then he would say that. He's an Aries.