Nicolas Guéguen and Lubomir Lamy placed collection boxes in stores every day for two weeks, and recorded the amounts given at the end of each day.
The boxes featured a photo of a starving woman and infant and read, "Women students in business trying to organize a humanitarian action in Togo. We are relying on your support."
Each box was identical, except for a call to action printed under the money slot.
Some boxes read, "Donating = Helping" under the slot. Some read, "Donating = Loving." And the rest had no call to action.
To assure store location didn't bias the study, the scientists relocated the boxes at random each morning.
The results after the two weeks were startling.
Every day, the boxes reading "Donating = Loving" attracted twice as much money as the other boxes.
"We can conclude that evoking love is a powerful technique to enhance people's altruistic behavior," the scientists said.
