It's sometimes not what we see, but what we do not...
A beverage station in an office in Newcastle, England, requires workers to pay for coffee, tea, and milk on the honour system. Money is supposed to go into a box - 30 pence for tea, 50 for coffee, 10 for milk. No hovering clerk stands nearby.
Researcher Melissa Bateson decided to turn this dispensing area into the central prop for a social-science experiment. She tracked how much milk was dispensed each week over a 10-week period and how much cash was collected. During odd-numbered weeks, the box received on average nearly three times as much as it did on even weeks for each litre of milk consumed.
What gave? On the odd weeks, Bateson affixed a pair of watchful eyes to the sheet of paper that listed prices. On even weeks, the eyes were replaced with a picture of flowers. When quizzed, none of the office workers remembered the images. But the simple presence of an iconic gaze seems to have made a big difference in how they behaved.