Let’s play a game!
We live in a society that relies on systems of exchange. Honest people exchange with each other but we need to constantly be aware of those individuals who may cheat the system.
So much so that evolution gave humans a heightened abilities to detect cheaters, whether it be in detecting facial ticks or through our judgment of a situation. The dominant theory in human evolution is that humans developed cheater detection due to the tit-for-tat (account-keeping) nature of exchange. If I give you something, you must give me something. Cheaters are those who fail to give something back and it was important to develop cheater detection to avoid these individuals, else we constantly lose out.
However, cheater detection may have evolved due to a more ancient and basic exchange system - need-based transfers. A system of exchange where people give to only those in need and only those in need may ask.
This project aims to compare humans’ ability to detect cheaters across different situations including both tit-for-tat and need-based transfer systems.
Riddle me this
The cards below have information about four situations. Each card represents one situation. One side a card has a number and the other side has a color.
The following rule holds: “If a card shows an even number one face, the opposite face is blue.”
What card(s) must you turn over to test the condition true?
If you guessed the first and last card, then you are correct! If you didn’t, do not feel discouraged as it was found that when framed in this abstract manner, less than 10% of participants answer correctly.
Now what if we change up the framing to the following:
“If you borrow my car, then you have to fill up the tank.”
Which card(s) must you turn over to test the condition true?
Much easier?
What if we change the framing again? This time the rule is:
“If you can pay for Chinese takeout, you don’t ask your friend for money. “
Even easier?
the project
When the problem is framed in the social contract situation, much like the Chinese takeout example above, people are much better equipped to detect those who cheat i.e those who ask for money for Chinese takeout when they already have money. In hunter-gatherer societies, cheater detection is much more important as resources are limited and having less than necessary could prove disastrous.
To test this hypothesis, I designed a variation on the previous game, this time framing the rule in a need-based transfer setting. If you need resources, you may ask. However, if you do not need, you may not ask. Can people still detect cheaters in this scenario? If they do, are they better able to detect cheaters than in a, say, tit-for-tat situation?
the data set
To test this hypothesis, I set up 4 variations of the game:
Abstract version
Tit-for-tat or account keeping
Need-based but the cheater is one who does not five when they are able
Need-based but the cheater is asking when not in need
Below are the percentages of people who provided a correct response to each treatment
The result
When a social contract is framed as a need-based transfer system, respondents can detect cheaters as well or better than when such a contrast is framed as a tit-for-tat reciprocity system.
Need-based transfers offer an alternative explanation for the explanation of the evolution of the human ability to detect cheaters on social contracts.
This project was a part of my undergraduate senior honors thesis in conjunction with Rutgers University and Arizona State University as a part of the Human Generosity Project. The thesis defense was one of two theses in the department to attain the classification of “Highest Honors.”
The project was presented at numerous symposiums and conferences, namely the 2015 Human Behavior and Evolution Society Conference.