How to defeat the impulse buy

THE Thanksgiving week heralds the holiday shopping season. Once again, a day traditionally meant to celebrate gratitude will inaugurate a month of rampant consumerism.

As a psychologist who studies decision making, I'm acutely aware that marketers know how the mind works, and they aren't hesitant to use that knowledge to stoke consumers' desires and lessen their self-control. Tactics emphasising scarcity ("only 10 televisions at this price in stock") and delayed cost ("zero per cent interest until 2016") are employed to great effect.

Such tactics prey on one of the mind's greatest vulnerabilities: the innate human preference for rapid reward, or immediate gratification. Most people, for example, would opt to receive $20 today rather than $100 in a year, even though, logically speaking, an investment guaranteed to quintuple your money in 12 months is hard to beat.