Tit for tat

Fairness in exchanges

An eye for an eye, a tooth for a tooth

You get what you give

What goes around comes around

One good turn deserves another

You scratch my back and I'll scratch yours

People tend to treat you the way you treat them

Trading favours


Judge not, and you will not be judged; condemn not, and you will not be condemned; forgive, and you will be forgiven; give, and it will be given to you; good measure, pressed down, shaken together, running over, will be put into your lap. For the measure you give will be the measure you get back.

Jesus Luke 6:37-38


“The norm of reciprocity is universal.”  If we do a favor, we expect one in return.  If we receive a favor we cannot return, we are distressed.

Donald W Pfaff, PhD – “The Neuroscience of Fair Play”


Reciprocity, in its various forms, is a fundamental principle of human nature and is the basis for mutually beneficial relationships.  It serves proportionately to reward helpful behaviour and punish harmful behaviour; to show people how we feel about their actions towards us; and to show them what their actions towards others feel like when you are on the receiving end.

Reciprocity is an ethical norm: an expected standard of behaviour.  When we do wrong, we are expected to try and put it right.  If someone does us a favour, we feel an obligation to repay them.  

It feels good for both parties if we do someone else a favour.  Because of the evolutionary history of human beings (interdependence and cooperation), in this situation we subconsciously expect to receive a benefit in return.  This is the case even when we anonymously benefit a stranger whom we can never meet or communicate with.  

Reciprocity thrives on repeated encounters – on long-lasting relationships.  These were the conditions that prevailed when our ancient ancestors lived and survived together in small groups on the African savannah.  For these people, as ourselves, reciprocity was a way to survive.  


Fairness in exchanges

Proportionality is a form of fairness.  In reciprocal exchanges, we expect proportionality, where a response is judged to be in proportion to the action that triggered it.  



Varieties of reciprocity



This is the simplest form of reciprocity: what you do to me I do in return.   

Tit-for-tat is the form of reciprocity used in trade and business.  

In personal relations, it is the normal mode between people who do not know each other well, who do not have an interdependent relationship.  Therefore it is more dominant within large groups (where many people are strangers) than in small groups (where people tend to have long-lasting interdependent relationships).  

Sometimes, let it go

In conflict situations, tit-for-tat is a dangerous way to proceed.  On the one hand, it is necessary to meet force with force.  On the other hand, at some point it is necessary to stop the merry-go-round of back-and-forth recrimination, for the sake of long-term prosperity for both sides.  

An eye for an eye and a tooth for a tooth leads to a land of people with no eyes and no teeth.  Try to meet anger with peace, strength, humility, and solutions, instead of more anger and drama.  Find out why the person is angry, and try to do something about the problem, rather than being tempted to “blow up” in kind.  


For every ripple you push away, you’ll create a thousand more

and the ripples will turn to waves

that will swell and break and overwhelm you.

Steve Taylor – from “The Harmony of Things”


“Immature” ego defenses are designed to get under your skin; don’t do the offender’s job for them by not being able to let go of an emotional response.

See also: attitudinal reciprocity, kindness spreads, Montagu Principle, grey rock


Credit: Frans B M de Waal – “How Animals Do Business” – Scientific American, April 2005

Symmetry-based reciprocity is described by the Stakeholder model of altruism.



Compassionate outcome

The bad situation needs to be brought to an end quickly and with compassion for the best interests of all concerned, aiming to protect the aggressor from their own foolishness and from continuing to make things worse for themselves.  

It is wise to treat people as if they are well-meaning and intelligent, instead of the stupid evil scumbag they might appear to be.  Instead of condemning them, educate them to be a better person.  “Love the sinner, hate the sin.”



Unconditional love

In the personal sphere, there are normally two situations in which unconditional love arises:  1) within the family;  2) within “symmetry-based” reciprocity.  In symmetry-based reciprocity, there are two people who share a common goal: it may be surviving or getting through life.  Since one person depends on the other, or each person depends on the other, it makes sense for one side to help the other, without needing any direct or immediate return.  Therefore, within unconditional love, the appropriate response to wrong or mistaken behaviour is correction and forgiveness rather than punishment and judgement.  Within the family, the common goal is effectively formed by having common genes, and the effective goal of genes is survival.  



Mathematical game theory, cooperation, reciprocity and forgiveness

Reciprocity can be studied using computer simulations.  Two computer-simulated agents play a game together over many rounds, where in each round, each agent can either "cooperate" with the other, or "defect" (refuse to cooperate), based on what the other did in the previous round.  The aim is to see, for various different strategies, how long it takes for mutual cooperation to fall apart.  The winning strategy has been found to be "hopeful, generous and forgiving".  Hopeful means that you need to start the interaction by being cooperative, and hope that this will encourage the other party to cooperate in return.  Forgiving means that if the other person defects, you will work hard to rebuild a working relationship of cooperation.  Generous means not to be too worried about getting exact returns for what you have put in, but instead be pleased to be engaged in a cooperative relationship where everybody benefits.

On the computer it is found that if you forgive 100% of the time, cooperation quite quickly falls apart and this is not a successful strategy.  If you always forgive bad behaviour, there is no incentive for the badly behaved person to behave well, and since they are not interested in mutual cooperation, the working relationship cannot continue.  

Islands of cooperation

In hostile, dog-eat-dog environments where people are fighting rather than cooperating, those who want to cooperate need to stick together to form “islands of cooperation”.



Reciprocity is a survival skill in hunter-gatherer societies


During the voyage of the Beagle when the young Charles Darwin first encountered the “savages” living in Tierra Del Fuego, he was amazed to realize that “some of the Fuegians plainly showed that they had a fair notion of barter ... I gave one man a large nail (a most valuable present) without making any signs for a return; but he immediately picked out two fish, and handed them up on the point of his spear.”  ...

When a person acts generously or responds to a generous act, the dopamine-associated pleasure centre in their brain is activated.  ...


In hunter-gatherer societies, reciprocity is used to create and maintain social networks, some of them very wide.  


When [Ju/’hoansi, African Bushmen] still roamed across the semi-arid Kalahari, with no way to store food, these people understood that their most important resources were their reputations and the stored goodwill of others.  ...

For those who store social obligations rather than food, unspoken contracts beginning with the most fundamental one between the group's gatherers and its hunters, and extending to kin and as-if kin in other groups tide them over from shortfall to shortfall.  Time-honored relationships enable people to forage over wider areas and to reconnect with trusted exchange partners without fear of being killed by local inhabitants who have the advantage of being more familiar with the terrain.  When a waterhole dries up in one place, when the game moves away, or, perhaps most dreaded of all, when a conflict erupts and the group must split up, people can cash in on old debts and generous reputations built up over time through participation in well-greased networks of exchange.

The particular exchange networks that [Polly] Wiessner studied among the Ju/’hoansi are called hxaro.  Some 69 percent of the items every Bushman used knives, arrows, and other utensils; beads and clothes were transitory possessions, fleetingly treasured before being passed on in a chronically circulating traffic of objects.  A gift received one year was passed on the next.  In contrast to our own society where regifting is regarded as gauche, among the Ju/’hoansi it was not passing things on - valuing an object more than a relationship, or hoarding a treasure - that was socially unacceptable.  As Wiessner put it, “The circulation of gifts in the Kalahari gives partners information that they ‘hold each other in their hearts’ and can be called on in times of need.”  A distinctive feature of human social relations was this “release from proximity.”  It meant that even people who had moved far away and been out of contact for many years could meet as fondly remembered friends years later.  Anticipation of goodwill helps explain the 2008 finding by psychologists at the University of British Columbia and Harvard Business School that spending money on other people had a more positive impact on the happiness of their study subjects than spending the same amount of money on themselves.

In her detailed study of nearly a thousand hxaro partnerships over thirty years, Wiessner learned that the typical adult had anywhere from 2 to 42 exchange relationships, with an average of 16.  Like any prudently diversified stock portfolio, partnerships were balanced so as to include individuals of both sexes and all ages, people skilled in different domains and distributed across space.  Approximately 18 percent resided in the partner's own camp, 24 percent in nearby camps, 21 percent in a camp at least 16 kilometres away, and 33 percent in more distant camps, between 51 and 200 kilometres away.

Just under half of the partnerships were maintained with people as closely related as first cousins, but almost as many were with more distant kin.  Partnerships could be acquired at birth, when parents named a new baby after a future gift-giver (much as Christians designate god-parents), or they could be passed on as a heritable legacy when one of the partners died.  Since meat of large animals was always shared, people often sought to be connected with skilled hunters.  This is why the best hunters tended to have very far-flung assortments of hxazro contacts, as did their wives.  

Contacts were built up over the course of a life well-lived by individuals perpetually alert to new opportunities.  When a parent died, his or her children or stepchildren inherited the deceased person's exchange partners as well as kinship networks, and gifts were often given at that time to reinforce the continuity, since to give, share, and reciprocate was to survive.  Multiple systems for identifying kin linked people in different ways, increasing the number of people to whom an individual was related.  One kinship system was based on marriage and blood ties, while another involved the name one was given, which automatically forged a tie to others with the same name.  These manufactured or fictive kin were also referred to as mother, father, brother, or sister.  

Such dual systems function to spread the web of kinship widely, and since the second system can be revised over the course of an individual's lifetime, it becomes feasible for a namesake to bring even distant kin into a closer relationship when useful.  Every human society depends on some system of exchange and mutual aid, but foragers have elevated exchange to a core value and an elaborate art form.  People construct vast and intricate terminologies to identify kin and as-if kin, in order to expand the potential for relationships based on trust.  Depending on the situation, these can be activated and kept going by reciprocal exchange or left dormant until needed.


Sarah Blaffer Hrdy – “Mothers and Others – the evolutionary origins of mutual understanding”



Public or secret reciprocity  

If we believe that by making a big show of getting back at somebody, we are justifiably demonstrating the size of their crime to the general public, we are probably mistaken that this is a good move, since the general public may not either know or care about the “crime”, and we just look like a “bad guy”.  

Indirect reciprocity

How I treat you depends on how you treat others.  It requires communication for one’s actions to become well known.  You may have to wait a while before the benefits of your good actions come back to you.  

“Bus driver gives a homeless man a £5 note – has his generosity rewarded by good Samaritan”  

The Independent, UK, 10 December 2015



Giving for the sake of giving, without thought of return.    


generosity ... is at the heart of give and take in human attachments.

Penny Spikins – “How Compassion Made Us Human – the evolutionary origins of tenderness, trust & morality”


Unconditional helping.  

Treating others as you would wish to be treated.  

“I recognise your predicament, therefore I want to help you.”  

Loyalty and obligation

Loyalty (commitment and affection) is willingly given for having been given services and help, or because someone’s existence is helpful to us (see also: stakeholder principle).  

Personal obligation can be resented.  For this reason, it is often bad manners to give someone a gift that is too extravagant.  

When something takes us closer towards thriving, surviving or reproducing, we feel a warm positive emotion.  So when another person helps us, we feel a warm positive emotion, or regard, towards them.  We also wish to help them in return.  


Gratitude is free happiness.  




Generalized warmth and gratitude ("upstream reciprocity")

Kindness spreads.  Studies have shown that if we are kind to someone, they are more likely to go on to treat others with kindness.  The result is a kinder environment for everyone.

People like to imitate each other, and to imitate what works best.  



Kindness produces more kindness

Maia Szalavitz and Bruce D Perry MD, PhD – “Born for Love”


Ye are the salt of the earth: but if the salt have lost his savour, wherewith shall it be salted? it is thenceforth good for nothing, but to be cast out, and to be trodden under foot of men.

Ye are the light of the world.  A city that is set on an hill cannot be hid.  Neither do men light a candle, and put it under a bushel, but on a candlestick; and it giveth light unto all that are in the house.  Let your light so shine before men, that they may see your good works, and glorify your Father which is in heaven.  

Jesus – Philippians 2: 13-16


Generalized bad feelings (upstream reciprocity)

Similarly, meanness and unkindness tend to spread.  Being mean or unkind to someone makes it more likely for that person to treat others badly, as well as oneself, leading to a degrading of kindness in the environment.


Attitudinal reciprocity

We instinctively mirror the attitude of the person who is addressing us.  

“Your attitude affects my attitude”


Emotional contagion

In humans, emotional suggestion is a powerful shaper of social behavior.  We’re exquisitely tuned in to the body language, facial expressions, and tone of voice of those around us, and will unconsciously mimic and synchronize these outward expressions of emotion.  

“Wild Justice – the moral lives of animals” by Marc Bekoff and Jessica Pierce

Our attitude is written all over us for all to see plainly, via our body language and emotional affect.  


Attitudinal reciprocity – positive or negative feelings

“I feel a warm positive regard towards you because you benefit me, therefore I want to help you”

“I have a feeling of dislike towards you because you harmed me, therefore I do not want to help you”  




Interdependent or friendship reciprocity

(dependence and interdependence)

"What's good for you is good for me."  


Emotional reciprocity occurs in long-term relationships where one party needs or depends on the other (dependence), or both parties need and depend on each other (interdependence).  Since person B benefits person A on an ongoing basis, person A feels a warm positive regard for person B and wishes to help and support them on an ongoing basis.  This is the proximate or psychological motivation for helping in this case.  

Importantly, what appears at first to be costly for the giver actually brings them benefits in the form of increased fitness for the person they depend on, which of course in turn brings increased fitness for themselves.  This is the ultimate or evolutionary motivation for the present-day psychological one.  

Emotional reciprocity describes the give-and-take between friends.  This kind of reciprocity is thought to be the prevailing one in intelligent social creatures like birds and mammals.  We believe it is beyond the cognitive abilities of non-human animals to set up and fulfil long-lasting contracts and take part in repeated, proportionate exchanges of goods and services, which is the classical tit-for-tat model of reciprocity.    

It can be described by the “stakeholder model”:  “I have a stake in your well being”; “I need you”.   See also unconditional love, cooperation, interdependence.  

Evolutionary ancestor of tit-for-tat reciprocity?

A reciprocal relationship is an interdependent one.  Human cooperation occurs within the context of interdependence, and reciprocity is a form of cooperation.  

It is very plausible that the evolutionary beginnings of the businesslike human tit-for-tat reciprocity were in the long-term, emotionally reciprocal, interdependent relationships between friends in our great ape ancestors.  

“Upstream reciprocity”  (i.e. downstream reciprocity)

How you treat someone influences how they go on to treat others.  


... in late 2007 the science media widely reported a study by zoologists Claudia Rutte and Michael Taborsky suggesting that rats display what they call “[upstream] reciprocity”, providing help to an unrelated and unfamiliar individual, based on the rat’s own previous experience of having helped by an unfamiliar rat.  Rutte and Taborsky trained rats in a cooperative task of pulling a stick to obtain food for a partner.  Rats who had been helped previously by an unknown partner were more likely to help others.  

Marc Bekoff and Jessica Pierce – “Wild Justice – the moral lives of animals”


Upstream reciprocity may be thought of as the Golden Rule combined with reciprocity: “when I was in this person’s position, someone helped me, therefore I will help this person”.  




Chimpanzees tend towards social reciprocity;  

Frans de Waal – “Chimpanzee Politics”