" Nevertheless, scholars keep obsessing about selfish motives, simply because both economics and behaviorism have indoctrinated them that incentives drive everything that animals or humans do. I don’t believe a word of it, though, and a recent ingenious experiment on children drives home why. The German psychologist Felix Warneken investigated how young chimpanzees and children assist human adults. The experimenter was using a tool but dropped it in midjob: would they pick it up? The experimenter’s hands were full: would they open a cupboard for him? Both species did so voluntarily and eagerly, showing that they understood the experimenter’s problem. Once Warneken started to reward the children for their assistance, however, they became less helpful. The rewards, it seems, distracted them from sympathizing with the clumsy experimenter.50 I am trying to figure how this would work in real life. Imagine that every time I offered a helping hand to a colleague or neighbor—keeping a door open or picking up their mail—they stuffed a few dollars in my shirt pocket. I’d be deeply offended, as if all I cared about was money! And it would surely not encourage me to do more for them. I might even start avoiding them as being too manipulative. It is curious to think that human behavior is entirely driven by tangible rewards, given that most of the time rewards are nowhere in sight. What are the rewards for someone who takes care of a spouse with Alzheimer’s? What payoffs does someone derive from sending money to a good cause? Internal rewards (feeling good) may very well come into play, but they work only via the amelioration of the other’s situation. They are nature’s way of making sure that we are other-oriented rather than self-oriented. "
― Frans de Waal , Mama's Last Hug: Animal Emotions and What They Tell Us about Ourselves