When I’m standing at a busy junction and the little man is red, I press a button and a sign lights up saying WAIT, so I wait.
And eventually the little man changes to green and I cross.
I press the button even though I suspect it doesn’t do anything.
I can’t believe they would interrupt the flow of traffic for a single pedestrian, but I press the button and wait anyway.
I do it because sometimes I’ve been at that crossing when there hasn’t been much traffic, and I’ve pressed the button and the light’s changed straight away.
Consequently, even though I suspect the button doesn’t do anything, I’m not sure.
So I go along with it – I press it and do what it says.
I’ve just found out this is what’s known as "a placebo button".
In central London, and other towns, it doesn’t do anything between 7am and midnight.
All it does is light up a sign saying WAIT.
During the hours of busiest traffic, the button is just a placebo.
But during the hours of less traffic, midnight to 7am, the button switches to manual and it does change the lights.
This is why people, like me, find it does work sometimes.
The New York Times reports that of 3,250 pedestrian buttons at traffic signals, 2,500 were deactivated in 2004.
They’re left in place because pedestrians still feel compelled to press them.
This is what computer scientist Eyton Adar calls a "benevolent deception".
He and two Microsoft researchers wrote a paper on it.
Ellen Langar, a professor at Harvard, refers to it as the "illusion of control".
She first noticed it during a game of five-card draw.
She dealt the cards, but out of order, and the players were outraged.
Each believing that the other player had got their cards and this had affected their chances.
Even though they had no way of knowing what the cards were.
She then studied the different ways people threw dice, believing they could affect the numbers that came up.
She even studied the way people pulled the levers on slot machines, believing they could affect the random rotation of the drums on the machine.
It’s the belief that doing something is better than doing nothing.
So, having chosen to press the button at a traffic intersection, we are more likely to obey the instruction to wait.
We need to believe the placebo.
And, as we know from medicine, the belief in a placebo is often powerful enough to affect the perceived result.
Often without proof from any exterior evidence.
It’s exactly the same way with advertising and marketing.
The need to believe in a placebo overrides a need to look for proof.
The need to believe in something becomes a dependence.
So we have the need to believe in big data, in AI, in VR, in content marketing, in storytelling – whatever the latest trend is.
But our belief in the placebo is so fragile, any doubt must be mocked and treated as heresy.
The placebo must be beyond question.
This is normal human behaviour – this is what religion depends upon.
We believe in something simply because we want it to be true.
Simply because it gives us a reassuring feeling of control.
In the outside world, this superstition costs nothing and does no real harm.
But in the world of advertising and marketing, this superstition kills creative thinking and costs many millions of pounds.
Dave Trott is the author of Creative Mischief, Predatory Thinking and One Plus One Equals Three.