Your irrational mind

Like it or not, you're not the beast of reason you think you are. Dan Ariely, a behavioural economist at MIT, argues that we're surprisingly and predictably irrational. Sex, freebies, expectations, placebos, price -- they all cloud our better judgment in rather sobering ways. Dan's unique research was partly inspired by a catastrophic accident which caused third degree burns to 70% of his body. He joins Natasha Mitchell in conversation.